Minerals

6 Rarest Crystals in the World

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AI generated model of a crystal in different colors
AI-generated model of a crystal in different colors. (Fotor)

Humans and crystals have been together for quite some time. The earliest records of crystals being collected by humans can be dated back to over 100,000 years ago. However, as technology improved, humans gained more information on naturally occurring crystals found beneath the Earth’s surface. 

As of now, there are over 200 known varieties of crystals and gemstones. Along with some of the most precious crystals, including ruby, diamond, and sapphire, there are numerous other crystals, and some of them are incredibly rare. 

This post looks at some of the world’s rarest crystals, in no particular order of rarity. 

Pink Star Diamond

AI-generated image of a pink diamond
AI-generated image of a pink diamond (Fotor)

This crystal is the rarest of the rarest when it comes to diamonds and it is one of the most valuable gemstones on the planet.

It is known for its extraordinary pink color and only a few of these have ever been discovered.

 

This diamond weighs 59.60 carats (11.92 gm). It was mined by De Beers in 1999 in South Africa and was sold for a record-breaking price of $71.2 million at an auction in 2017.

Tanzanite

TanzaniteTanzanite is one of the most beautiful blue crystals, a variety of a mineral named zoisite; however, the crystal doesn’t get its name from the mineral. Instead, it is named after the location of its discovery which is a small area near the foot of Mount Kilimanjaro in Tanzania. So far, it is the only known source of the crystal, which makes it rare and extremely valuable. 

Since its discovery in 1967, the crystal has gained popularity among jewelers and gemstone enthusiasts. However, according to estimates, the reserves of this precious crystal would last for only 20 to 30 years before the supply deletes, which will make the stone significantly more rare and valuable than diamonds unless a new source is discovered.

If you look at the properties of this crystal, it ranks between 6 and 7 on Mohs’ scale of hardness which makes it ideal for everyday wear. Moreover, its highly prized blue color may closely resemble blue sapphire, a favorite crystal for jewelry. However, heat treatment can significantly enhance its blue coloration, making it more unique and strikingly beautiful. Since there is only one known source of the crystal, Tanzanite is a highly valuable crystal with an average per-carat price of $1,200 for top-quality crystals.   

Poudretteite 

Another extremely rare crystal is Poudretteite which was discovered during the 1960s by the Poudrette family at their quarry near Mount St. Hilaire in Quebec, Canada. The crystal was named after the name of the family that first discovered it. However, the crystal was not officially recognized as a new mineral until 1986. Hence for a long time, there were no reported discoveries of Poudretteite. 

Several decades later, a gem-quality specimen of the crystal was first documented in Burma. Since then, only very few crystals have been found. The crystal is so rare that clean crystals over 1 carat are hardly ever found. Moreover, the largest known Poudretteite weighs 9.41 carats. Since it’s very rare to find a crystal of this weight, the largest known Poudretteite sits at the Smithsonian National Museum of Natural History.   

Benitoite 

Benitoite, the state gem of California, is another rare crystal that is only mined in a small area of California near the San Benito River. Hence, the gemstone got its name Benitoite. The crystal was first discovered in the early 1900s by the geologist George D. Louderback.

However, it was not until 1985 that the crystal became the official gemstone of California. The major source of the rare crystal near the San Benito River was closed for commercial mining in 2006. While trace quantities of the crystal were discovered in Japan, Australia, and Arkansas, California is the only known source that allows feasible mining of the crystal, making Benitoite another rare crystal in the world. 

Benitoite has a deep blue color that shows unique fluorescence when caught under UV light. If you want to purchase this rare crystal, make sure you find a trustworthy and legitimate source. Moreover, you need to go for stones with a medium body tone and a cut that enhances the stone’s fire. Crystals that are too dark in color will not reflect the light well. Similarly, a color that is too light will have a washout-out appearance. Furthermore, you shouldn’t expect to find stones that are heavier than 3 carats. 

You can find a high-quality medium blue Benitoite with an average price of $3,800 per carat. Stones that are less than 1 carat will have a relatively much lower price. 

Black Opal 

Coobe Pedy Opal Doublet Mineral
Coobe PedOpal Doublet Minera

Opals are usually creamish-white and can display rainbow-colored inclusions as light reflects on the stone. However, black opals are different and rare. Most of the black opals are mined in the Lightning Ridge area in New South Wales, Australia. Since it is extracted from a single source, black opals are the rarest of all opals found in Australia. 

Black opals have a naturally black body color. However, you can also find variations of the stone in green, blue, and brown colors. 

The most precious black opals are the ones with a darker color and brighter inclusions and the most precious black opal of all time is known as the “Aurora Australis,” which was found in 1938 in the Lightning Ridge area. The 180-carat black opal had an estimated worth of $650,000.  

Taaffeite 

Last on the list is another rare crystal, Taaffeite, which is also considered the rarest crystal globally. As of now, there are only 50 known specimens of this rare crystal, and most of them are held in private and geological collections. 

The crystal was discovered by chance by Austrian-Irish gemologist Edward Taaffe. Hence the crystal got its name. In 1940, the geologist bought a box of spinels, but he noticed that the mauve-colored spinel didn’t react to light in the same way as the rest of the spinels did; he sent it for further examination. The results revealed that the mauve-colored spinel was an unknown gemstone with no known source.

A few years later, Taaffeite was announced as a naturally occurring mineral. As a result, several other collectors re-examined their spinel collections and found a few more rare crystal specimens. Finally, the crystal source was tracked down, which revealed that most of the crystals came from Sri Lanka, whereas a handful was also found in China and Tanzania.

Conclusion

This brings an end to the list of the six rarest crystals in the world. There are several other rare crystals, such as Alexandrite, Padparadscha sapphire and many more that will hardly ever make an encounter with the general public, but they will continue to be rare and precious crystals that will be of immense value to people. 

Geology

Novarupta – The Most Potent Eruption of the 20th Century

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Image by Kanenori from Pixabay

It happened on June 6th, 1912!

The Novarupta-Katmai volcanic eruption in Alaska in 1912 became one of the most powerful eruptions of the 20th century. Even 109 years later, its status as one of the largest volcanic eruptions still remains.

In this post, we look at how it happened and the possibility that history might repeat itself again. 

The Eruption

On the morning of June 6th, 1912, Alaska residents were getting ready to start their upcoming fishing season. Back then, the population in the Alaska Peninsula was much lower than it is today. However, a few things never change, and earthquakes in the region are one of them. Even at that time, earthquakes were common in Alaska because of the region’s geological instability. 

As people were used to living in the region, over time, they realized that the earthquakes were not only getting more frequent but also stronger. Because of the frequency and intensity of these quakes, the two remaining families in the village left their homes for a safer place. 

And that’s when it happened. Around midday on June 6th, the skies over Katmai darkened and what happened next continued for the next 60 hours. The area didn’t see the sun during all these hours of a continuous volcanic eruption. 

Throughout the 60 hours of the constant eruption, the volcano spewed out around 6.7m3 of ash particles around 20 miles into the stratosphere (which extends around 30 miles above the earth’s surface). The ash-covered an area of around 3000 sq. miles, and the ash fell in amounts up to a foot that changed a nearby vast green valley into a wilderness known as the Valley of Ten Thousand Smokes. 

Impact of the Eruption

The region’s inhabitants were among the first people to experience the direct impact of the eruption. It was so loud that the blast was heard around 750 miles away. Moreover, the impact was not limited to sound. It had a major visual impact as residents witnessed a thick cloud of ashes that quickly rose towards the sky. 

Within the first few hours, this thick layer of ash began falling from the sky onto the nearby town of Kodiak. As the eruption continued for the next three days, the ashes covered the town up to one foot deep. As a result, the region’s inhabitants were forced to take shelter indoors as the outdoor environment was suffocating, making it difficult to breathe. The damage further continued as some of the buildings collapsed due to the heavyweight of the volcanic dust.

The impact was not limited to that region either. Within the next few days, the ash cloud traveled over western Canada and to several western U.S. states. By June 17th, the cloud was found in Algeria and then continued to spread to other regions, including China and India. While there were no deaths reported from the eruption, there was a lot of indirect impact in terms of loss to plants, animals, marine life, and agriculture, which continued for several years. 

The Formation of Valley of Ten Thousand Smokes

Novarupta Volacano
Valley of Knife Creek. Erin McKittrick, Ground Truth Trekking

Following the eruption, the National Geographic Society started sending expeditions to Alaska to investigate the damage.

During one such expedition in 1916, a few researchers traveled inland to the eruption area and found out that the valley of Knife Creek was completely barren.

Moreover, the ash was still hot, and thousands of jets of steam could be seen from the ground. Inspired by this observation, the valley was known as the “Valley of 10,000 Smokes”.

The Resulting Katmai Caldera and Novarupta Dome

During the initial observations, the Katmai Caldera volcano was originally thought to be a source of the eruption. However, it was a long time after the incident that researchers identified the original source as the Novarupta volcano. 

Can History Repeat Itself?

Novarupta is now silent and has been for quite some time. The last eruption reported from this volcano was the one in 1912 however, if you look at the history of Novarupta, it has erupted at least seven times in the last 4,000 years. Moreover, since the Alaska Peninsula is located on an active convergent boundary, we can expect future volcanic eruptions. Furthermore, given the location of Novarupta, it is likely that future volcanic eruptions will have a severe local and global impact, similar to what happened to Pompeii in 79 AD from the Mount Vesuvius volcano.

The local impact of potential volcanic activity anywhere can lead to a significant loss of life. Due to the potential impact of volcanic activity in this area of Alaska, the United States Geological Survey and others are closely monitoring these volcanoes. 

Furthermore, the impact of any future eruptions can have a devastating effect on the global climate. Studies indicate that a volcanic blast of this magnitude can modify the global surface temperature patterns and rainfall levels in several parts of the world.

Another possible reason to monitor these volcanoes is the danger of any future eruption on commercial air traffic. Jet engines experience enormous air pressure, and flying through the air containing fine ash particles can have a similar effect as sandblasting, which can cause extensive damage to the aircraft. Therefore, it is estimated that any future eruptions from Novarupta halt commercial air traffic across North America.

What Can We Do About It?

Unfortunately, eruptions like Novarupta are one of the natural disasters that we cannot prevent. However, the most we can do to control the situation is to assess the potential impact and develop a plan of action to minimize losses. With a history to look back to, there is a lot that we can learn from the eruption of 1912 and improve our chances of minimizing damage, injury, and death.

Minerals

What is Iron?

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What is Iron?

Iron ore in rock form
Iron ore on a rocky base

Did you know that iron is a healthy nutrient for our bodies as well as the main ingredient in the manufacture of steel?

Before we venture into the types of iron, let’s first examine its properties. Iron is a mineral with the symbol Fe and atomic number 26.

On the periodic table, it belongs to the first transition series, which reflects a change in the inner layer of electrons, but we’ll leave that for the chemists since the chemical compound of this mineral is beyond the scope of this article.

Iron is the most common element on Earth when referenced by mass and is very prominently found in the Earth’s outer and inner cores. It is the fourth most common element in the Earth’s crust, but the process to extract it requires kilns or furnaces capable of reaching a temperature of 2,730 °F or higher.

A Little Bit of Iron History

Bronz Statue
Bronze Statue
Wikipedia_Public Domain

Durint the Bronze Age (c. 3300–1200 BC) it was the metal of choice to create art, tools, and weapons. It was the first time metals were used for these purposes. Prior to this period, stone was used as a tool and for weapons; hence, the Stone Age.

Interestingly enough, the Bronze Age also brought us the first writing system and the invention of the wheel. An intriguing period of creative thought for sure.

Enter Iron

Say goodbye to bronze and hello to iron; hence, the Iron Age, which started around 1200 BC. It should be noted that before the Iron Age was coined, there were occasions when iron was found to be used much earlier.

One historical account was that of the ancient Egyptians. Archeologists found iron beads made from meteorites dating back to 3200 B.C.  Iron is abundant in outer space. But these incidences were rare until the time when iron became the metal of choice.

Iron for Infrastructure

Steel Columns and beams of 1 World Trade Center
Steel  (an alloy of iron) columns and beams of One World Trade Center Under Construction. Photo: SS

Once we entered the 19th century, new uses for iron materialized. It was discovered that this mineral, when mixed with carbon, can be used for building purposes, and with the advent of the industrial revolution, where items were being mass-produced, the manufacture of iron became an economical commodity. 

Building Construction

Iron in its pure form, it is not used for building construction since it would not have the tensile or compressive strength required for infrastructure, but when other elements are added to it, such as carbon, it can become a desirable metal.

Bridges and buildings are just two of the common uses of iron alloys, since their tensile and compression strengths are bolstered. Let’s take a look at the iron alloys.

Cast Iron

Cast iron buildings NYC
Cast iron buildings, Lower Manhattan. Photo: SS

Cast iron has 2% to 4% of carbon mixed in with it along with some small amounts of impurities, such as sulfur and phosphorus.

This alloy has an advantage as it is simple to cast (mold).

A good example of the use of cast iron can be found in the SoHo and nearby areas of New York City. There are about 250 cast iron buildings located there. The initial purpose of cast iron facades was to improve older buildings, but they were eventually used in newer construction as well. 

Cast Iron’s Disadvantage

Because of iron’s brittleness (subject to fractures under stress) and relatively low tensile (ability to stretch) strength, cast iron is not a suitable material for products that require a high degree of tension or bending moments.

Cast Iron’s Advantage

Although tension is not a good quality of cast iron, it does have acceptable compressive strength (ability to sustain heavy loads) and it is also durable (ability to withstand wear).

Construction of bridges and buildings using cast iron was very popular in the late 19th and early 20th centuries. In fact, there is a whole section in New York City that is called the Cast Iron District, also known as SOHO.

Later in the mid-20th century and on to today’s building construction techniques, cast iron gave way to steel because of the fact that steel has high tension capabilities as well as high compression.

Wrought Iron 

Cast iron fence. Palermo Italy
Wrought iron fence. Palermo Italy. Photo SS.

Wrought iron is not an iron alloy. It is made entirely of iron with no  carbon additions. Wrought iron is malleable, ductile, and corrosion-resistant. 

This metal is different from cast iron and because of its malleability. it was given the name wrought since it could be hammered into shape while it remained hot. Wrought iron is a prerequisite to mild steel, also called low-carbon steel, and is considered the first of the steel alloys.

As a matter of fact, the element was initially refined into steel. In the 1860s, ironclad warships and railways were built with these iron alloys.

Wrought iron was eventually halted to make way for the less expensive and stronger steel, as steel’s advantage over wrought iron and cast iron is its ability to absorb shocks without breaking.

Steel

Steel Cantilever at Chase Bank Headquarters
Steel Cantilever at Chase Bank Headquarters Under Construction. Photo: SS

Steel is an iron alloy that contains a low amount of carbon, roughly 0.40%; however, that is enough to change iron’s characteristics, and with the advent of the Bessemer process, making steel became less costly to create. 

Steel has good tension and compression factors, as well as being impact resistant. Steel is so strong that it is used to cantilever skyscrapers. This is why you see so many buildings under construction today that have steel as their framework.

Iron for Nutrition

Red Blood Cells
“Red blood cells” by rpongsaj is licensed under CC BY 2.0

Since iron is a mineral, it is also an important nutrient for our bodies. If you have an iron deficiency, you may possibly acquire anemia and also fatigue.

So how much iron do you need on a daily basis? For most people, an adequate amount of iron is consumed daily via the foods that we eat, but to determine your specific iron needs, you can see a chart and information here. One person told us that he eats yogurt and raisins every day. Raisins contain a certain amount of iron. 

Do you know why our blood is red?  It is because there is an interaction between iron and oxygen within the blood creating a red color. Learn more about red blood cells and iron here.

To be sure you have enough iron in your body, check with your doctor to confirm you are not deficient.

Conclusion

Besides being an essential component for healthy blood in our bodies, iron became an essential component for weapons and later, building materials.

There are differences between cast iron and wrought iron besides their carbon content. Cast iron is created using the casting method, where a liquid metal is poured into a mold, while wrought iron is made by use of heating and bending.

Numerous bridges and buildings have been constructed during the 18th, 19th, and 20th centuries using iron, but as the industrial revolution advanced and the making of materials became automated, new alloys of iron were created, specifically, steel and along with concrete, led to the construction of stronger buildings, bridges, and skyscrapers we see today all over the world. 

Geology

6 Longest Non-Polar Glaciers Around the World

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Glaciers, large masses of dense ice, are formed in high-altitude regions where the accumulation of snow is far greater and faster than the melting process. Over time, the layers of snow crystallize and form ice. The process of formation of glaciers takes centuries and even millennia. Surprisingly, glaciers are not just a unique feature of the polar caps but they are also found in many non-polar regions of the world. High mountain ranges in the former USSR, Pakistan, and the Americas are also home to some of the world’s largest non-polar glaciers. Below is a list of the seven longest non-polar glaciers in the world.   

Fedchenko Glacier, Tajikistan 

The world’s longest glacier outside the polar world is the Fedchenko glacier situated in the Central Asian country of Tajikistan. The glacier is around 45 miles long and covers an area of 350 square miles. The Fedchenko Glacier flows north from the ice field of Revolution Peak and receives ice from dozens of other smaller glaciers. The thickness of ice in the middle of the Fedchenko glacier is approximately 3,280 feet. The giant mass of ice can cover a distance of up 26 inches every day and forms the headstream of River Surkhab and the Amu Darya. 

It was discovered in 1871 by a Russian expedition and is named after the Russian explorer A.P. Fedchenko. Parts of this iceberg were explored later in 1928. Over time, the glacier has experienced a significant loss of ice. Climate change and global warming have dramatically reduced their size since the second half of the last century. 

Siachen Glacier, Indo-Pak Border 

The Siachen is the second-longest non-polar glacier in the world lying in the Karakoram Range near the border of India and Pakistan. It is 47 miles long and covers an area of 270 square miles. The region is home to many smaller glaciers and a number of fast-flowing surface streams.  

Climate change has significantly affected almost every part of the world and the Siachen glacier is no exception. Between the years 1989 and 2009, this area of ice was reduced by 2.2 square miles. Human presence in the region has further accelerated the melting, as this mountain of ice has been a source of conflict between military conflict for decades. The highest battlefield on Earth provides freshwater which enters the River Indus of Pakistan and the Ganges in India.

Biafo Glacier, Pakistan 

The Biafo Glacier is another long non-polar glacier located in the Karakoram range in Pakistan. The 40-mile-long mountain in Gilgit-Baltistan meets Hispar Glacier, another 30-mile-long glacier, and forms the largest glacial system outside the polar region. This ice formation acts as a bridge between the two ancient kingdoms of the mountains; The Nagar and Baltistan. The Biafo glacier provides a trek with spectacular sights and traces of wildlife all along.  

The glacial system is largely affected by the changing global climate. The rising temperature has destabilized the movement of these ice formations and has altered the level of rain and snowfall in the region; consequently, these changes have resulted in flooding and intense heat waves not only in Pakistan but in other neighboring countries as well. 

Bruggen Glacier, Chile 

The Bruggen Glacier, also known as the Pio XI Glacier, is located in southern Chile. With a length of 40 miles, it is the fourth-largest glacier in the non-polar region and the longest glacier in the Southern hemisphere.  The glacier continued to advance towards the sea and covered a distance of more than three miles between 1945 and 1976. 

Despite being one of the largest glaciers in the nonpolar region of the world, the Bruggen glacier is one of the least studied glacial areas in the world. However, considering its pattern of movement, it can be concluded that the glacier experienced periods of enhanced movement followed by retreat periods. This effect is in addition to climate change which is negatively affecting the glaciers around the world. 

Baltoro Glacier, Pakistan 

The Baltoro glacier is located in the mountain range of the Karakoram in the Baltistan region of northern Pakistan. It covers an area of 23 square miles and the length of the centerline is more than 35 miles. The second highest mountain in the world, K2 is located around 7 miles north of the tongue of the main glacier. 

Despite its location in a remote and politically unstable region of Pakistan, this glacier is extensively studied by geologists. This glacier is of unique importance to geologists because of its extensive debris cover. 38% of the area of the glacier is covered with debris. When it comes to these types of ice formations, debris accumulation follows a certain pattern of increasing thickness. Ongoing land sliding and mudflow have led to an increase in the thickness of debris in the Baltoro glacier. As of now, the debris thickness in Baltoro glaciers has reached almost 10 feet, which is a major concern for geologists. 

South Inylchek Glacier, Kyrgyzstan, and China 

Another tourist-friendly destination, the South Inylchek Glacier is located on the borders of Kyrgyzstan and China. With a length of over 60 miles and more than 300 square miles, the Inyichek glacier is the sixth-longest nonpolar glacier. It is divided into two sections and covers more than 100 peaks of varying heights with snow and ice. 

It is a place of incredible natural beauty where climbers around the world can enjoy the trek along with breathtaking aerial views. 

 

Astromony, Technology

Life in Outer Space and the UFO Phonenomena

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Milky Way Galaxy
Photo by Arnaud Mariat on Unsplash

Is There Intelligent Life Out There?

One of our previous articles discussed the minerals of Star Trek, giving rise to the hope that there is extraterrestrial life out there, but the honest discussion about ET’s existence is a loaded subject. 

For this article, we are going to focus on the probability of whether life exists in outer space; in other words, what are the odds that there really is intelligent life on other planets?

As difficult as it is to wrap our heads around the sun’s fusion process, which is equivalent to 100 billion atomic bombs per second, we will go one step further and try to understand the immense size of our universe, and then look at the formulas that scientists have developed to determine ET’s existence.

2023 Update on Extraterrestrial Life

It was already known that one of Saturn’s moons – Enceladus has oceans, but its Cassini spacecraft just recently found that its oceans contain the element phosphorus, which is a key chemical element in the building blocks of life.

This brings us one step closer to finding out if life exists right in our own backyard.

But what about intelligent life?

So What Are the Odds?

It is estimated that there is an average of 1 – 2 billion stars in any recorded galaxy and there are over 2 trillion galaxies out there. If 10% of each galaxy contains a solar system, that is, it contains a star that has planets revolving around it, then we can estimate that each galaxy has between 100 – 200 million solar systems, with some that may be fairly similar to ours.

AI creation of space alien
Illustration Courtesy of Hotpot.ai

If 1% of the stars in each solar system have a planet just distant enough from their sun where life could evolve, called the habitable zone or as some scientists call it, the Goldilocks Zone, we could have 1 – 2 million possible planets that could contain life.

Going further, if 1% of these planets have the right ‘ingredients’ to build intelligent life, then there is the possibility that there may exist 10,000 stars that could have planets with intelligent life in each galaxy.

Just to be more realistic, we can cut the odds even further and take 10% of this result, which would equate to the possibility of 1,000 stars with extraterrestrial life in each galaxy.

That would mean that there could be 1,000 x 2 trillion galaxies = 2,000,000,000,000,000 (2 quadrillion) planets with intelligent life. How many is that? Just take a look at this numerical comparison; thus, If we use the estimate of two trillion galaxies in the universe, that would mean ET may live on over 2 quadrillion planets in our universe.

Don’t even try to comprehend how many fusion reactions occur here every second when you include all of these stars. Fuhgeddaboudit!

What About the Scientific Formulas?

The above calculations were based on a general layman’s assumption, but have the experts given the possibility of extraterrestrial life serious thought?

American astronomer and astrophysicist Dr. Frank Drake developed a formula that he presented at a meeting in Virginia in 1961. It is called the Drake Equation, which calculates the possibilities of life on other worlds within our own Milky Way galaxy.

Drake Equation
Nasa Photo

We won’t go into the calculations, but in a general sense, it is based on our assumptions above but uses trigonometry to formulate a much more explicit and precise determination of ET’s existence. For you science and math connoisseurs, feel free to give it a shot below!

The terms are as follows:

N : The number of planets in the galaxy where electromagnetic emissions are detectable
R: The rate of scanability to have exoplanets with habitable Fnes revolve around them
fp : The fr those stars that have solar systems
ne : The number of planets in each solar system within the Goldilocks Zone
fl  :r of planets on where life may exist
fi : The number of planets where intelligent life may exist
fc : The number of planets that have civilizations with a technology where we can detect their signals
L : The length of time that these civilizations have produced these signals

What About the UFO Sightings?

Now we come to the discussion of UFOs. If life does indeed exist, are they here or not?

Where are the Pictures?

Illustration of a space ship with human hands reaching out to it
Photo: iStock

Dr. Neil deGrasse Tyson, astrophysicist and Director of the NYC Hayden Planetarium at the Rose Center for Earth and Space had an interesting thought.

He said with all the cell phones that people have these days (which account for hundreds of millions), not one person has come forward with a clear picture of a UFO, alluding to the assumption that if there is life in outer space, they most likely have not reached us.

We are sure Dr. Tyson believes that intelligent life does exist, but he is being realistic in suggesting that ET still has to come here before he calls home.

What About Worm Holes?

Dr. Tyson’s view is the opinion of one expert and his statement is by no means conclusive. With that said, Dr. Tyson welcomes the opinions of other experts in the field, such as his colleague theoretical physicist and CUNY Professor Dr. Michio Kaku, who advances to theories beyond current reality and states that aliens could be here by way of quantum computing. (To see the complete discussion of Dr. Tyson and Dr. Kaku, check out our article on quantum computing).

The Quantum Link

We earthlings are only at the fetal stages of quantum computing, but Dr. Kaku suggests that it’s quite possible that extraterrestrial life has already harnessed quantum computing and in so doing, they have been able to obtain the answer to many questions that have baffled humans for mellimena. One such question would be is – how did the big bang happen?

Moreover, if they are able to tackle that question, there is no doubt that they also have been able to determine how a wormhole operates. A wormhole is a phonenoma that allows one to travel from one end of the galaxy to the other or event from one galaxy to another in a matter of minutes.

If this is the case, then perhaps ET is already here and with their advanced capabilities, they could easily cloak themselves from the vision of us Earthlings and if Dr. Kaku’s theories are correct, maybe, just maybe the suggestions of aliens in Men in Black are right!

Conclusion

It is mostly a unanimous decision by scientists that extraterrestrial life does exist and there is agreement that there also is intelligent life out there somewhere, so the question is are they here on Earth or not? And that is where there are still open discussions.

But regardless if they are here, would they look like us? If not what would they look like? Another interesting dilemma to consider!

Geology

What is Concrete?

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What is Concrete?

Concrete Blocks
Photo by uve sanchez on Unsplash

Ever notice that just about every building has a concrete foundation?  There is a very good reason for this and it is not about aesthetics. Concrete has enormous compressive strength, meaning that it is an excellent material for holding up the weight that is above it. 

Concrete is not just used for foundations, but also for columns, and beams. slabs and just about anything where there is a load-bearing issue. Load bearing means an element that supports the weight above it. The amount of weight that the load-bearing element would support would depend upon how many concrete columns (or other concrete supporting materials) are available to support the whole load.

For example, a 30-story building has 10 supporting columns on the ground. That would mean that the weight is evenly distributed across each of the 10 columns or mathematically speaking, each concrete column would support 0.333 (10/30) of the load (building).

Another probably more identifiable example is the load-bearing walls in a house. If you live in a house, you have probably become aware of where your load-bearing walls are. These are the walls that actually hold up the house; however, for frame houses, concrete is not the usual load-bearing material, but heavy wood or steel instead. 

A concrete column
Concrete column supporting the highway above. Photo by SS

In short, concrete is an excellent source for withstanding the heavy forces that are above it or more specifically, as an excellent compression material.

Did you know that concrete also gains more strength as it ages? With that said, let’s take a look at just what this compressive material is actually made of.

What is Concrete Made Out of?

Concrete is a mixture of air, water, sand, and gravel and the percentages of these elements are usually 20% air and water, 30% sand called fine aggregates, and 40% gravel, with 10% being cement; that is, 10% being the ‘glue’ that keeps all those other materials together. Remember, from our article on cement, it is just the binding material for the assembly of concrete. When the cement is mixed with water, it is called paste. 

This proportion is called the 10-20-30-40 Rule; however, the exact percentages of the materials can vary depending on the combination of the concrete mixture, including the type of cement and other factors that we will explain in this article.

How are the Proportion of Materials that Form Concrete Determined?

So we know that concrete is a mixture of paste and aggregates and sometimes rocks. The paste coats each of the aggregates and as it hardens (the process is called hydration), concrete is born until it becomes a rock-solid mass, capable of withstanding a load much heavier than itself, but if the proportion of water and paste is not correct, this rock-solid mass can deteriorate causing unwanted and potentially dangerous consequences.

The trick is to carefully proportion the mix of the ingredients and much of it depends on the ratio of water to cement and this ratio is calculated by the weight of the water divided by the weight of the cement. A low water-content ratio yields high-quality concrete, so it is best to lower the ratio as much as possible without sacrificing the integrity of the concrete.

If the ratio results where there is too much water in the mixture, the aggregates become thinned out, resulting in weakening the concrete and we can figure out what that would mean.

Conversely, If there is not enough water in the mix, the water will evaporate too fast, compromising the integrity of the concrete and resulting in it being weak as well.

Construction worker worket pours concrete into rebar frame
Construction worker pouring concrete into steel rebar frame. iStock

What is the Strongest Concrete Mixture Ratio?

1:3:5 which is cement and aggregates (in this case, the aggregate is broken into sand (3) and gravel (5), and this is considered the ratio that would create the strongest concrete.

What Happens if the Wrong Mixture of Concrete is Used?

If the ratio of the concrete mix is not done correctly, there can be a variety of problems, such as compromising its integrity which can lead to disastrous results.

Cracking

Excessive water content, inadequate curing, or incorrect proportions of cement, aggregates, or water can contribute to cracking. These cracks can compromise the durability of the building and allow moisture penetration, leading to further deterioration over time.

Reduced Strength

Concrete strength is a critical factor in ensuring the structural integrity of buildings. If the concrete mix has an incorrect ratio of the required additives, it may not achieve the strength needed to maintain its load. This can compromise the load-bearing capacity of the structure and lead to collapse or deformation under normal loads.

Ultimately, using an improper concrete mixture poses safety risks to occupants and users of the building. Structural failures or deterioration can lead to accidents, injuries, and even loss of life in severe cases.

Champlain Towers Building Collapse

Surfside florida condo collapse
Miami Beach Surfside, FL, June 26, 2021, Champlain Tower collapse most probably due to concrete deficiencies.

One recent incident occurred in Surfside, Florida where the Champlain Towers collapsed on June 24, 2021, and 98 people lost their lives.

The investigation is still ongoing but they have found structural defects in the design of the pool, as well as compromised integrity of the columns that supported the building.

How Much Time Is Allocated Before the Finished Concrete Is Used at the Construction Site?

There is a limit to how long the concrete can be poured after it is mixed. In the US, the limit is 60 minutes from the time the water mixes with the cement to the time of delivery to the construction site.



A safe time frame is up to 90 minutes, then the integrity of the concrete will start to deteriorate. That is why we see concrete mixers right at the construction site as no time is lost between the mixture and the pouring.

What About Reinforced Concrete?

As the name applies, when steel (usually using steel bars, called rebars) is placed inside the slab where the concrete is going to be poured, it reinforces the strength of the concrete.

How Does Rebar Reinforce Concrete?

We have been discussing compression strength; that is, how strong the material is when a heavy load is placed on it, but we haven’t discussed tensile strength, which is the opposite of compression.

Tensile strength represents the strength a material can endure when a force tries to pull or stretch it out. The reason why compression is so important when using concrete is that that is its main purpose – to hold up heavy loads, but concrete does have a limit on how much pull can be leveled on it as well, and there are situations where the tensile strength of concrete is put to the test. The weather being one factor, but there are more.

Enter Steel

Reinforced Steel Slab
A construction worker working on a reinforced steel slap where the concrete will be poured. Photo by SS.

By integrating the rebars inside the concrete, the concern about stretching the concrete is greatly minimized. The combination of concrete and its accompanying reinforcing steel bars successfully manages these situations, because of steel’s high tensile strength; hence, you have a perfect storm of compressive and tensile strength in reinforced concrete (RC).

What Happens if the Reinforcing Steel is Not Inside the Concrete?

Cracking of the concrete surfaces can occur, subsequently causing aesthetic issues, but if the tensile yield is really great, (e.g. a strong pull on the concrete) the situation can become unsafe, so without the steel rods to compensate for this pull, you will find cracks in the concrete or worse.

Conclusion

Concrete is a mixture of sand, water, aggregates and cement. The amount of any of these elements will determine the strength of the concrete. Timing also plays a role as the concrete must be readily mixed within 90 minutes max, but 60 minutes is the usual requirement before being poured into its foundation or another element such as a column or slab.

By placing steel bars which is a mesh of steel wires (rebar) inside the concrete, the tension issue is resolved by aiding the concrete under tension.

So the next time you are walking in a building, especially a large structure such as a skyscraper, give thanks to the materials that allow you to be there, as well being thankful to the engineers who allowed it to happen!

 

Geology

How Cement is Made?

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What is Cement?

Solider pouring the fine powdery cementIf you were to say “I tripped on a cement block”, would you be wrong?

The answer is yes because there is technically no such thing as a ‘cement’ block, but there are concrete blocks; that is to say, cement is nothing more than the ‘glue’ that binds the materials that make up the concrete block, which is usually sand and gravel. So if you were to say “I tripped on a concrete block”, you would then be correct.

According to Wikipedia, cement “sets, hardens and adheres to other materials to bind them together.” In simple terms, cement is the centerpiece of what keeps the concrete intact. 

What Materials are Cement Made of? 

The sand and gravel are called aggregates, and it is these materials that are bound together but remember, cement is not the material, it is the glue. So what makes up the cement? 

The ingredients are mainly limestone and clay, which are extracted from quarries from around the world. Of course, the process of making cement is not that simple. The limestone is heated with clay to 2,640 °F in a kiln (an insulated chamber). This process is called calcination, which liberates molecules of carbon dioxide from the calcium carbonate (the main ingredient of limestone) to form calcium oxide, commonly referred to as quicklime. 

It is here where the quicklime chemically combines with the other materials to make a hard substance, called ‘clinker‘. Gypsum is then added to make Portland cement, the most common type of cement used, which is referred to in the industry as OPC. 

How does the Limestone Mixture Process Work?

The limestone rock is crushed in a machine appropriately called a crusher which reduces the limestone to a size of about six inches maximum. It is then fed into the second crusher where it is further reduced to under three inches. The mix is conveyed and then sent to a raw mill bin to be ground down even further.  

In these bins are two chambers. One that dries the limestone and clay mix and the other that grinds it via hot gasses. Then, once all dry, it is moved to the grinding chamber called a ball mill.  Here a cylinder contains steel balls and rotates which causes the balls to fall back into the cylinder and onto the limestone mix; hence, grinders. 4 to 20 revolutions per minute is the general rotation of the cylinder, which is dependent upon the diameter of the ball mill.

A Newcome Engine

What’s left when the grinding process is done is a product of fine and coarse material. The coarse material is useless in that state and is called reject where it is returned back to the ball mill for additional grinding. A machine called a separator does this part. 

Having the limestone and clay grounded down to a fine powder is still not enough to complete the cement process. The mixture must then enter a device called a cyclone which is used to separate the fine grounded material from existing gases that still exist in it.

Then, the hot gas and fine materials enter a multistage “cyclone”. This is to separate the fine ground materials from the gases.

The result – a clean, fine powdery material and is renamed kiln feed. 

Next, the feed is heated via a process called sintering, which is when the chemical bonds of the material are broken down using heat, and once complete, a new substance is formed called clinker.

Clinker nodules for the production of cement
Clinker nodules produced by sintering at 1450 °C. This is the intermediate process for the production of cement

The clinker is initially very hot and contains small, dark gray nodules from 1mm to 25mm in size where it is placed into a grate cooler for cooling from approximately 2550 °F to approximately 240 °F via the use of cooling fans.

And voila! You have cement!

Final Note

Other elements are added to the clinker depending upon what the cement is going to be used for. In the case of Portland cement, gypsum is the additive.

And you thought that making cement was just adding powder and water. We hope you gained some good knowledge as to how cement is actually created. And the next time you get angry after you trip over a block that’s made up of limestone and clay, you know that it is concrete you take your anger out on and not the cement that put it together.

 

 

 

Geology

How Buildings are Constructed Along Earthquake Fault Lines

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Transamerica Pyramid San Francisco
Earthquake resistant Transamerica Pyramid, San Francisco. Photo Wikimedia CC

One of the first structures built to withstand an earthquake was the Transamerica Pyramid, also called the Transamerica Tower. In this seismically active region, no engineering was spared to keep the building safe from earthquake tremors.

Located on 600 Montgomery Street, it rises 853 feet and 48 floors and was the eighth tallest building in the world in 1972. On the highest floor, 48, there is a conference room that has unobstructed 360-degree views of the San Francisco Bay area.

The building has a wide base that narrows upwards, much like the churches and buildings of antiquity, which is designed to give the structures their stability. No doubt this is an optimum method for buildings that reside along earthquake fault lines. From an environmental perspective, the pyramid design (hence the name), allows natural light to filter down to the streets below.

Looking to limit the degree by which the structure would twist and shake during an earthquake, engineers used a unique truss system with built-in steel, reinforced concrete, precast quartz aggregate and glass. It has two angular setbacks working their way up to the top of the tower and a 212-foot spire. There are two angular concrete structures on the east and west sides that protrude from the 29th floor rising upwards called wings. The wings are part of the structural engineering that went in to keep the building sturdy during an earthquake, but they also have a function. The eastern wing serves as an elevator and the western wing includes a staircase.

To reinforce the building even more, there is a truss system on the ground and lower floors which are designed to support both vertical and horizontal stresses. Truss designs are cross beams engineered to perfectly distribute the weight of a structure in order to withstand tension (pulling) and compression (pulling) forces.

Modern building with external truss system
Buildings with external truss systems are able to manage torsional (twisting) forces generated by seismic events. Photo by Ricardo Gomez Angel on Unsplash

Under the truss, beams are X beams over the ground floor, designed to brace the building against any type of torque movement.

This torque and stress reinforcement was tested in 1989 during the .71 magnitude Loma Prieta earthquake. The building successfully withstood the quake with no damage and no injuries.

 

In addition to above-ground stress reinforcement, there is an additional basement from earthquake tremors, consisting of a 9-foot deep concrete mat foundation, which lies on top of a steel and concrete block that goes 52 feet underground. This foundation contains 16,000 cubic yards of reinforced concrete, including over 300 miles of steel reinforcing rods. This concrete assists with the additional support of Compressive stress and tensile stress.

The Pyramid is a self-contained structure, which has its own 1.1-megawatt power system. Construction began in the fall of 1969 with the first tenant moving in in 1972 and is still standing gracefully today as a monument to earthquake building construction.

 

Geology

The 2 Methods to Building a Subway

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Subway tunnel construction in NYC
Subway tunnel construction in NYC  (Photo: wirestock – www.freepik.com)

For those who love big cities (and even smaller ones), there’s no doubt you have ridden on one of their mass transit lines. With that said, have you ever wondered about the amount of engineering that has gone into building one? Well, here we will give you some basic information as to how they are constructed.

There are two basic methods to subway construction: “cut and cover” and the other is called “deep bore.”  Cut and cover refers to the complete opening of the street, down to where the subway would be built and deep bore refers to the burrowing strategy previously discussed in our Tunnel Boring article.

To determine which method is going to be used, an engineering and environmental review is necessary, which includes logistics, underground water determination, earth material, demographics and of course, costs, not to mention the bureaucracy of working with the different city agencies to determine where all the utility lines, water pipes and potential other tunnels are located. 

This bureaucracy alone could take months or even years, And if any of these factors become obstacles, then additional planning would be required. The bottom line is that this whole procedure is a great undertaking and can get very complex. 

So with this introduction, let’s delve into describing the engineering process by which each of these methods would be used.

Cut and Cover Method of Building a Subway

Tunnel cut and cover method of construction of the Paris Metro
Tunnel cut and cover method of construction of the Paris Metro – Wikipedia Public Domain

This method is found in the building of some of the older subway systems, such as the Paris Metro, London Underground and the NYC subway. With this method, the pavement of the street is completely removed and then a hole is dug down into the ground. 

“Cut and cover” is considerably cheaper than the “deep bore” method; however, the dig must parallel the street, so there is no room for more sophisticated planning, like curved tracks that fork off to some desired locations, unless the street above does the same.

Another undesirable factor is that “cut and cover” results in large holes in the street significantly causing traffic nightmares, as well as major inconveniences for store owners along the route.

Deep Bore Method 

The boring machine is a sophisticated and expensive apparatus that cuts through the underground dit by using circular spinning blades. The advantage this has over “cut and cover” is that they do not have to follow the street grid above, allowing much greater flexibility in the design of the subway lines, as well as not have to dig big holes along the route. The boring method is slow, but efficient and cuts through the earth at a rate of about fifty feet per day. 

The disadvantages are that the costs are significantly higher than cut and cover, where $150 million would be a medium price. 

How the Subway Construction Method Is Decided

As mentioned, there are so many factors to consider when building a subway line, but the number of subway lines and the cost factors involved would be the major considerations.

For example: After extensive analysis of which method would be better to construct the Second Ave Subway in Manhattan, it was decided that the TBM would be more efficient, based upon the fact that cut and cover would cause so much economical damage, the boring method would be more practical, even though it is more expensive.

Preparation for TBM cutting head to be lowered into a tunnel
Cutting Head of a boring machine being lowered into the hole where a tunnel is to be constructed. Photo by david carballar on Unsplash

Just lowering this giant machine into the tunnel is a major task, not to mention expense, but it is worth it in the case of big-city construction.

Another major consideration was the amount of interruption and financial damage the cut and cover method would have caused, especially on a congested and commercial road like Second Ave. where the upper east side and midtown Manhattan would be commercially interrupted.

Considering how often there would have been complaints, especially in this time period, where community demonstrations are the norm, more and more TBM usage is becoming the preferred method, so as not to disturb life above ground. However, cut and cover construction may still be considered if the soil conditions are not up to standard.

Building the Second Ave Subway NYC
TBM in action during the building of New York’s Second Ave Subway (Google CC Flicker)

An example of how the political consequences of cut and cover road disruptions can escalate, take a look at Vancouver B.C.’s recently opened Canada Line. A lawsuit was taken against the city of Vancouver and the plaintiff, a retailer with a store along the subway route where won C$600,000 after cut and cover caused major financial hardship. Following that lawsuit, an additional 41 plaintiffs have taken legal action to recover financial damages. 

What the Future Holds

We are now in the 21st Century and with technology streaming at a rocket pace (e.g. artificial intelligence, at home video conferencing, sending a man to Mars) it will only be time before new engineering technologies will lead to faster, lighter and much less expensive boring machines. Then if you think some cities have excellent transportation facilities now, wait till these new machines come along and open the door to even more elaborate and reduced financial expense.  

 

 

Precious Metals

Understanding the Geology of Silver

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10 Gram Silver Bar
10 Gram Silver Bar

Silver – Overview 

This soft, white, precious metal is valued for its beauty and industrial uses. It has a history that goes back as far as 4,000 B.C. Around the same time, techniques to refine silver and separate it from other metals were identified and practiced. As research on natural elements progressed, silver got its chemical name and secured its position in the periodic table in group 11 and period 5. For our science enthusiasts, this malleable metal has the following element properties: 

    • Atomic Number – 47
    • Atomic Weight – 107.8
    • Melting Point – 1,861.4oF
    • Boiling Point – 4,014oF
    • Specific Gravity – 10.5
    • Luster – Metallic
    • Mohs Hardness – 2.5 to 3 

Because of its rarity and high industrial demand, silver is considered a precious metal with a high economic value. Its physical properties make it the best possible metal for various uses in a wide variety of industries. 

For starters, it has electrical and thermal conductance that is higher than any other metal, which makes it valuable in the electronic industry.  Silver is also sort after because of its exceptional ability to convert ethylene into its oxide, a prerequisite of many organic compounds. However, it is the least reactive of the transition elements.

Moreover, it has better reflectivity at most temperatures. Finally, its color and attractive finish make it a desirable choice for coins, tableware, jewelry and many other objects.

Given its uses and properties, silver is often the material of choice. However, unlike other precious metals, the value of silver is often not reflected in the price, which makes it one of the most underrated precious metals.

Let’s take a closer look at how silver is found in nature.  

The Geology of Silver 

The precious metal occurs in nature as one of the four following forms.

  • as a natural element; 
  • as an essential component of silver minerals; 
  • as an alloy with other metals; and 
  • as a trace element in the ores of other metals. 

Below we intend to understand the geology of the precious metal better.

Silver as a Natural Element 

Silver rarely occurs as a natural element. Instead, it is often found with other metals, including gold, copper, quartz and sulfides and other metals’ arsenides. In placer deposits, silver is rarely discovered in significant amounts. Because it does not oxidize readily, silver can also be found above the ores of other metals in its natural state. However, the precious metal reacts with hydrogen sulfide that results in a discolored surface, including silver sulfide, also known as acanthite. Researchers have found many specimens as a natural element that have been exposed and reacted with hydrogen, and have an acanthite coating.

Silver in this form is often associated with hydrothermal activity. In areas of abundance in this activity, silver can be found as cavity fillings. Some of these deposits are rich enough to support mining. However, mining for silver alone is often not feasible. Therefore, the economic viability of silver extraction depends upon the presence of other valuable minerals. For extraction of such deposits, an underground operation is undertaken that follows the veins and cavities where silver in its natural state is found. 

As an Essential Component of Silver Minerals

Close up of Silver CoinsThere is a surprisingly high number of minerals that contain silver as an essential component. There are over 35 different distinct silver minerals which include but are not limited to the following. 

  • Acanthite, 
  • Berryite, 
  • Chlorargyrite, 
  • Dyscrasite,
  • Empressite, 
  • Fettelite, 
  • Petzite, 
  • Samsonite

Each of the silver minerals is distinct and rare, however, a few silver minerals exist in quantities that warrant mining. Silver minerals can be found as silicates, sulfides, iodates, carbonates, oxides, nitrates and bromates. 

Alloys and Amalgams of Silver 

If you take a closer look at the placer deposits of gold, you will find gold alloyed with small quantities of silver. When the ratio between gold and silver reaches at least 20% silver, the alloy is called “electrum” which is a combination of silver and gold. When gold is refined and purified, that leads to the production of a significant amount of silver. Interestingly enough,  most of the silver available on the market today is a byproduct of gold extraction and purification.

The metal can also be found as a natural alloy of mercury, which is found in the oxidation zones of silver deposits. This amalgam of silver is also associated with cinnabar, which is a toxic mercury sulfide mineral. 

As a Trace Element in the Ores of Other Metals

The other most common source of silver is its occurrence as a trace element in the ores of other metals. It is often found along with other commonly extracted metals, including copper, lead and zinc and can be found as an inclusion within the ore. Moreover, it can be found as a substituted metal ion within the ore’s atomic structure. However, there is a possibility that the value of silver may exceed the value of the primary metal within the ore.

Silver – Extraction and Production Around the World 

Silver is found all around the world. Over 50% of its production comes from North, Central and South America. Other contributors of silver outside America include Russia, China and Australia. 

Silver deposits are usually associated with magmatic and hydrothermal activity. Major mineral deposits are therefore found in these regions. The association between geothermal activity and silver deposits is more pronounced in the Americas, where the silver production follows the Andes Mountain Range. In other parts of the world, the production of silver is related to igneous activity regardless of its geologic age, but a different trend has been observed in Europe, where silver production is associated with historic volcanic activity. 

Conclusion 

Silver is a precious metal with various industrial and commercial uses. While its worth is often not reflected in its economic value, silver still remains a rare, precious metal, given how it is found in nature. 

Howard Fensterman Minerals