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Minerals

Ammolite: A Marine Fossil Gemstone

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Ammolite are gem-grade fossilized shells of ammonites. They are known to have spectacular display of sparkling colors in the presence of reflective lights. Different variants of ammolite produces different spectrum of colors; some only reflect one or two colors. These fossilized remains are considered gemstones because they can easily contend the exquisiteness and color strength of established gemstones such as opals and labradorite.

Anatomy of Ammolite

When dissecting the anatomy of this colorful gemstone, one comes to know that ammolite are thin gleamed coverings of ammonite fossils. It should be noted that not all ammonite fossils have ammolite as their coverings. Two species of this extinct marine molluscs are festooned with this organic gemstone. Most of the present day ammolite deposits are found along the riverside of St. Mary in Alberta, Canada.  

Geological History of Ammolites

The host fossil of ammolite, ammonite was present in the waters as a living species nearly 70 million years ago. As their extinction started, the shell of dead ammonites fell to the bed of the seaway and gradually covered with mineral sediments resulting in the formation of gem-quality ammolites.

Ammolite: From Its Original Form to Gemstone

Transforming journey of ammolite from its original fossil form into a gem-grade entity is an interesting one. In the first step, the slender shell of ammonite fossil is removed from its dark shaded base. Since most of the ammolite strips are so delicate to handle therefore they are not subjected to any further processing to enhance the texture and color of the gemstone. Instead, ammolite receives the stabilization treatment. There are few steps involved in the process of stabilization:

    • The fragile specimen of ammolite is reinforced by adding thin block to its back. Usually darker color shale slabs serve this purpose
    • To protect the surface for which ammolite is known, covers of clear transparent minerals are used. Thin covers of spinel and quartz are used so that the surface of ammolite can be protected without affecting its beautiful natural display.

There is another relatively less used method to stabilize ammolite in which the specimen is soaked with an epoxy solution. Rare cuts of ammolites don’t require stabilization and can be used in jewelry in their indigenous form.

Quality Determination of Ammolite and its Uses in Ornamental Items

Apart from their size, there are few other characteristics of ammolite that determine its quality as a gemstone.

  • Ammolites that display more than one glowing color
  • Ammolites that display the phenomenon of iridescence from various angles
  • Ammolites with color bends that are not broken up by gaps are also considered very precious. Gaps are formed ammolite surfaces due to fractures and the inclusion of other minerals

Ammolites that fulfill all these three requirements are then cut and used in different type of jewelry. Capping or transparent covering of the stones is done as per the customer’s requirement. For instance, people who want to have the best and more natural view of ammolite will prefer less dooming. On the other hand, some people like this dooming because it enhances the visual character of the stone.

Ammolites that are totally uncapped or covered can be used in jewelry items such as earrings, pins, and brooches that are less likely to face abrasion.  

Historical Significance of Ammolite in Different Cultures and Religions

In Hinduism

Ammonites found in the fossil sediments of Gandaki River in Nepal usually show golden luminescence and have been used to show the characteristics of Vishnu and his chakra. This attribution of the stones earned itself veneration from Hindus.

In Native America

To the Niitsitapi nation of Native America, ammolite and other fossil stones are associated with an abundance of resources, healing and good fortune.

In Chinese Culture

The believers of the ancient Feng Shui philosophy recommend ammolite as the stone used to cure financial problems. Ammolite is also named after a mythological Chinese beast ‘Qilin’ and hence called Qilin or Kirin Stone. In Chinese tradition, ammolite is also attributed to traits of longevity and non-violence.

It is interesting to see that the same stone is revered in different geological locations and demographics for different reasons. However, it can be inferred that this shared reverence from different cultures and religions is there due to ammolite’s unique iridescence.

Minerals

Extraterrestrial Gemstones

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Extraterrestrial Gemstone

Extraterrestrial objects and beings have been both fascinating and frightening to human beings for centuries. Among them, the ones that have fascinated us are extraterrestrial gemstones.

These stones or rocks are made of very rare metals and minerals and possess a great deal of significance for collectors and geologists. The rock and stones are fragments from extraterrestrial objects that landed on the earth or they were created due to the impact of meteorites.   

What Actually Are Extraterrestrial Gems?

These are meteorites whose impactites are small enough to be used as gems. But that is not the only condition for any extraterrestrial object to be classified as a gem. They should look attractive and pleasing to the eyes as well. Here are a few interesting facts about them:

    • Sometimes, meteorites contain more than two metals, like an alloy. They can be used as extraterrestrial ornaments and gems. For instance, alloy meteorites of iron and nickel are cut and polished into beautiful-looking objects.
    • Meteorites with peridot crystals embedded in them can also be cut into the shape of beautiful gems.
    • Meteorites are rich in silicate are also shaped and polished into the form of cabochons.  

Rare yet Inexpensive

There is no doubt that these ET specimens are very rare in their existence, yet they are not as expensive as some of the popular gemstones. There are two major reasons for this contradiction:

    • Many people are still unaware of this phenomenon where meteorites can be transformed into beautiful gemstones.
    • There is no proper meteorite gemstone market. There is no supply chain for such gemstones and even those that is available in the market are not reliable enough.

Types of ET Gemstones on the Basis of Demand

Not all ET stones are equally sought-after by the people who are interested in collecting and researching such species:

    • Stones that can be used in the same condition in which they fall from the sky are the most expensive type of ET gemstones. Scientists, collectors and jewelers, all want to get their hands on ‘as found’ ET stones.
    • ET stones with the best gem quality are also expensive and used by jewelers to make some limited edition ornamental designs.
    • ET stones with smaller sizes and low quality are usually treated as collectibles.

There are some famous ET gemstones and rocks that have captured the human imagination and have been put to different uses.

Desert Glass

These ET stones are a type of natural glass found in the desert, which has formed as a result of a meteor impact in the area. The glass is created from the silica abundantly found in the desert sand.

There are a few sites all over the world where desert glass can be found. The most popular subtype of this ET stone is known as Libyan Desert glass. Fragments of this desert glass are found in the eastern Sahara Desert.

Desert Glass of King Tutankhamen

The pendant from the pre-BC era shows that desert glass has been used by humans for thousands of years. King Tutankhamun, an Egyptian pharaoh of the 18th Dynasty buried with ornamental items containing desert glass. It shows that ancient Egyptians put this meteor stone in very high regard. The pendant found in the Tomb of the Egyptian King has desert glass as its centerpiece.

Popular for Metaphysical Properties

Even now, desert glass is used for its metaphysical properties. It is thought to have a great mystical power to strengthen your willpower. According to chakra energy principles, the golden yellow color of the glass vibrates in the band of solar plexus chakra which is associated with the willpower of any living body.

Moldavite

Moldavites are formed due to meteorite impacts in southern Germany. They are dull green fragments of meteorites that are considered gem-grade stones. In alternative medicine, moldavites are very popular due to their healing powers for the emotional and physical being of an individual.

Beware of Fake Moldavites

With its supposed health benefits and gem-like appearance, this ET stone has always been in demand. Due to the imbalance of demand and supply, people started to make fake moldavites from glass. Beware of these ‘glass moldavites’ and buy the original ones from a reliable meteor and mineral collector.

Small Meteorites: Used as Earrings

Small and distinctive shaped meteorites are also used by some to make hipster earrings by drilling a hole or with the help of wire wraps.  

 

Minerals

Corundum – Parent Mineral of Ruby and Sapphire

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Corundum Mineral StonePhoto by Epitavi – yayimages.com


Corundum is a mineral found in many metamorphic, sedimentary and igneous rocks. It is aluminum- based rock-forming mineral. Pure corundum ore exists in colorless form. The mineral gets its color majorly from iron and chromium impurities. Some other mineral impurities such as cobalt, nickel, and vanadium can also be found in the deposits of corundum. The mineral is known to possess high levels of hardness, therefore, it can easily be found in crystalline form in many different colors.

Even though corundum has been used by humans in different shapes and forms for centuries, the revolution in modern mining history of corundum happened when a geologist W.F. Ferrier pointed to the large deposits of corundum in Canada in his survey report in 1896. In a few years, the mining of corundum started in the communities of Ontario, Hastings colony and Carlow. Now corundum, both in natural and synthetic form is used for many purposes.

People know corundum by sapphires and rubies

People are familiar with this mineral through the gemstones of ruby and sapphires. Both of these precious stones are the variants of corundum. Finer grades of corundum in red hues are called rubies while the ones with blue shades are known as sapphires.

Physical properties of corundum

Corundum comes in the top three hardest minerals along with moissanite and diamond.  It is assigned with that hardness of 9 on Mohs scale. They get recognized by their distinctive physical properties. They possess high specific gravity and definite hexagonal crystalline structure. They also have a great tendency to cleave along stressed areas.

The history associated with the name ‘Corundum’

Most historians agree to the fact that the word ‘Corundum’ is derived from the Sanskrit word korund or Kurundum. Another fable associates the name with an ancient district of Karund in the state of Orissa, India. The deity of the region is Manikeswari, which literally means ‘goddess of rubies or corundum’.  This claim was also substantiated by the fact that the karund district was known for the deposits of the ruby gemstone.

The occurrence of corundum in Nature

Corundum can be found in many different geological settings and in all those rocks that are rich in aluminous instead of silica. Syenite, nepheline syenite and pegmatite, all of these igneous rocks contain corundum as their primary mineral. It is also found in metamorphic rocks derived from aluminous and carbonate sediments. Marble, schist and other products of regional metamorphism also contain corundum.

Some of the naturally occurring marble deposits contain gem-quality of vibrant colors and clarity. Due to its relatively inert nature and hardness, it is able to survive the extremes of weather and can be found in different alluvial deposits. Most of the higher grade corundum is obtained from the clay beds of different river deltas.  Word’s famous alluvial deposits of corundum are located in Cambodia, Sri Lanka, Afghanistan and India.

Corundum hardness: best suited for abrasives

The hardness of corundum makes it the best contender for abrasives for many industrial uses. Corundum is first crushed into smaller particles which are then processed to produce same-sized granules. The final product is used in different ways for the purpose of abrasion. It is used to make polishes, sandpapers, grinding wheels and other grinding media.

However, with more innovation and precision in the manufacturing process, some disadvantages of natural corundum started to appear. The particles of corundum are usually small and irregular in their sizes – this means the quality needed in the making of many products is not necessarily met.

Synthetic corundum, on the other hand, has consistent physical properties. It is made of calcined bauxite. Corundum in the form of emery rock has also been used as an abrasive in many industries. It is a granular rock rich in corundum, spinel, magnetite and hematite.

Corundum as a gemstone

Even though the use of corundum as an abrasive has declined in recent years due to the availability of better options, no one can take the place of corundum in the world of gem and jewelry because two of the ‘big four’ minerals are variants of corundum.

Diamond, ruby, sapphire and emerald due to their historical significance and aesthetic appeal are the four most sought-after gemstones in the world.

Minerals

Lapis Lazuli – a Heavenly Blue Rock Gemstone

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Lapis Lazuli Stones
Photo by richpav – yayimages.com

Lapis lazuli appears as a mineral, but according to geological classification, it comes under the category of metamorphic rocks. It is a blue rock gemstone that has served many purposes throughout the history. The rock of lapis lazuli is composed of many different minerals and its color is the result of the presence of blue silicate mineral called lazurite. Some other minerals such as white calcite and crumbs of pyrite are also part of the mix of lapis lazuli.

Origin of the Name

The name of this rock gemstone has its origin in Latin and Persian languages. ‘Lapis’ is a word from Middle Latin which means ‘a stone’ and ‘Lazuli’ is a genitive of ‘lazulum’. ‘Lazulum’ has been derived from a Persian word ‘lazhward’ meaning ‘blue’.

History of the Rock Mineral

Egyptians’ Obsession with Lapis Lazuli

The history of lapis lazuli is very fascinating because it has its roots in the pre-BC era. In ancient Egypt, this stone was considered to be one of the most prized tributes and rewards. Some of the oldest mines in Egypt date back to 4000 BC and interestingly, are still active sites of lapis lazuli mining.

It is referenced as sapphire in the Old Testament and thought to be one of the twelve stones embedded in the breastplate of the High Priest. Clothes of royalty and pastors are dyed with this rock gemstone to distinguish them from those of ordinary people. The golden coffin of the Egyptian king, Tutankhamen, was ornamented with lapis lazuli. The stone — due to its ultramarine hue —  is considered very important since it contrasts perfectly with the arid desert hues of the region.

In medieval Europe, lapis lazuli was considered a part of the heaven’s sky. It was used to repel evil spirits and considered sacred to get the blessings of the spirits of wisdom and light.

Geological Occurrence of Lapis Lazuli

Lapis Lazuli is formed when stones like marble and lime go through the process of metamorphism. During the process, the lazurite takes its place in the host rocks in the form of layers and stripes with other mineral additions to take the shape of lapis lazuli.

A rock must have a peculiar blue color and one-fourth of its part must be made of blue lazurite to be considered lapis lazuli.  The addition of calcite and pyrite are responsible for white and gold layers in the stone.

How Lapis Lazuli Rocks get Refined?

Many of the specimens of mined lapis lazuli are dyed in the finishing process before going into the market as sculpture base, ornaments and gemstones. They are dyed with blue color to remove the white shade created by the presence of calcite.

Uses of Lapis Lazuli

In Jewelry

Lapis lazuli is commonly used as an ornamental stone in pins, earrings and pendants. Lapis lazuli has a Mohs hardness of 5, which makes it unsuitable for jewelry items that face more abrasion such as rings and bracelets.

Lapis Lazuli: a Pigment

Lapis lazuli has been used as a high quality pigment for a long time. To make pure rich blue pigments, the rock is treated with soft acids to remove the minerals of calcite and dolomite that adulterate the blue color of the stone. The final product of lapis-rich pigment is then mixed with oils and other mediums to be used as high quality paint.

The Starry Night: A gift of Lapis Lazuli Pigment

For more than 100 years, the art and culture all around the world have been fascinated and inspired from the master strokes of Van Gogh in his one of the best artwork “The Starry Night”. The painting has a distinctive vivid blue backdrop which is there because The Dutch maestro used ultramarine lapis lazuli pigment for this oil on canvas painting.  Some other historical paintings of medieval times are also based on the pigment of lapis lazuli.

In alternative medicines, lapis lazuli is still used as the stone for its benefits of different healing energies.

Minerals

Topaz: A Mineral Made of Silica and Fluorine

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Photo by Epitavi – yayimages.com

Topaz is a silicate based mineral that occurs in different colors and shapes. It is usually formed in Pneumatolytic actions under the earth’s surface when gases pass over hot magma.  According to a research conducted by the University of California, Berkeley, during the final stages of solidification of igneous rocks such as pegmatite and rhyolite, the fluorine-rich vapors convert into crystals to take the form of topaz.

Cavities and fracture of igneous rocks are the usual sites of topaz formation and eventual extraction. The secondary deposits of topaz can be found in pebble sediments of streams with their origin in these igneous rocks.

Properties of Topaz

Topaz is one of the hardest known mineral stones. It possesses a hardness of 8 on the Mohs Hardness scale. Only diamond, chrysoberyl and corundum are harder than topaz given this criterion of hardness.

Most of the naturally occurring topaz stones are colorless or possess a milky tinge. Rare ones can be found with shades of orange, pink, red, blue and purple. These rare topazes are the ones used for ornamental purposes.

Topaz is fragile and easy to break. This contrasts sharply against the reading it takes on Mohs Hardness scale. The reason behind their fragility is a distinct basal cleavage that slices perpendicularly to the long axis of the crystal. The long axis of topaz is formed when it is grown unhindered in nature to take the shape of orthorhombic crystals.

Origin of the Name

There are two popular theories regarding the origin of the name ‘Topaz’. Many historians believe that the name comes from a Greek island in the Red Sea called Topazios. The interesting fact about this name origin is that, the island never produced topaz. Deposits of peridots, which were extracted from the island, were mistaken for topaz before the development of the subject of modern mineralogy. Another popular theory associates the origin of the stone’s name with Sanskrit word of topas or tapaz, meaning ‘fire’.  

Historical Significance of Topaz

The ancient Greeks were of the thought that wearing topaz offered strength. They believe that topaz could make soldiers invisible to enemies. During the age of Renaissance, Europeans firmly believed that topaz could be used to dispel magic spells. They were also used for the purpose of anger management. In India, it is worn as a part of a necklace to bring health and intelligence to the wearer. Romans considered topaz therapeutic for failing eyesight. They used to put topaz stones on closed eyelids as  treatment.

Uses of Topaz

Topaz with yellowish color display has been used for thousands of years as a gemstone. Few hundred years ago, it was realized that natural topaz can occur in a wide range of colors. As a gemstone, it has several uses.

Birthstone of November Babies

Other than citrine, yellow topaz is also the birthstone of those born in November. Wearing this birthstone is said to have many positive effects on the wearer. It can increase the capacity of the person to accept feelings of affection and reciprocate it.

Used for Positive Crystal Energy

There is an alternative school of thought that believes that crystals can emit energies with their particular effect on human beings. There are many supposed benefits of the crystal energy of topaz. For instance, it can be used to alleviate pains associated with arthritis and rheumatism. It is supposed to improve the functions of the endocrine glands. Topaz energy is also beneficial for eyes; it can ease eye strain, and improve eyesight.

Topaz as an Abrasive Material

Topaz naturally occurs in many shapes, colors and qualities. Lower grade topaz can be used as an abrasive in many industries and products. For instance, it is used in the making of scouring pads and knife sharpeners due to its abrasive qualities.

Treated Topaz Stones

Since colorful topaz stones are very rare in nature, colorless specimens are also subjected to different treatments to bring a desired color shade. They are subjected to heating and coating of metallic oxides on their surface. Different metallic oxides are used to produce different colors. These treated topaz stones are used to make different jewelry items.

Minerals

Geodes – A Natural Pouch of Stunning Minerals

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Geodes are spherical and semi-spherical rock structures that appear like any other rock from the outside, but are different on the inside. They have an internal cavity that is filled with a variety of minerals. The presence of different valuable minerals inside makes them look attractive. Therefore, these rocks are one of the most sought-after geological structures that professionals and collectors alike strive to acquire.

Natural Formation of Geodes

The formation of these special stones sounds like a tale of magic realism. Hollow cavities inside geodes are made when they take the shape of rocks from cooling magma or lava. Cavities are made inside rocks when a bubble of water vapor or carbon dioxide is formed in the flowing lava.

Cavities can also be made underwater when lava cools down to solidify in water. The outside surface of the melted magma solidifies before the inside. The liquid lava trapped inside causes the newly solidified crust of rock to leak. Once all the liquid has leaked out, a hollow space is left inside.

After the cavity is formed inside the geodes, the treatment of mineral-rich groundwater starts. Water accumulates a thin layer of minerals inside the cavities by seeping through porous rocks. It is imperative to mention that the process of mineral accumulation take a lot of time. The buildup of minerals gets transformed into crystals and this can take thousands of years. Some large crystals can take even few million years to grow into their final shape.

Geodes are special and rare geological structures and cannot be found in every rock formation. They are usually found in those areas where rocks are formed in a peculiar geographical environment.

Most geodes deposits are found in:

  • Stratified volcanic deposits of tuffs and basalts
  • Sedimentary carbonate deposits of dolomites and limestone

Small amounts of geodes can be extracted from some other rock formations as well.

Which Minerals Stones are Present in Geodes?

Not all geodes are lined with the same type of mineral residue. However, tiny quartz crystal and agate are mostly found inside geode cavities. But there are geode deposits that are lined with more precious minerals.

Purple amethyst, white calcite crystals, pink rhodochrosite, opals with spectacular play of color and colorful agates are also found inside some rare geodes. Geodes don’t have a definite size. Their size can vary from few centimeters to several meters.

Utilities of Geodes

Until they are unopened, there is no general interest in these stones. However, when they are opened and the inner lining of these stunning minerals becomes visible, then they become the center of attention for many reasons.

Collector-quality Geodes

After determining the quality of minerals present inside, there are some geodes that are sold in auction and with astounding price tags. The price of rare geodes can easily race up to five digits. Affluent people with a hobby of precious stone collection take interest in those collector quality geodes.

Geodes:  Decorative Tools

Large pieces of geodes that are mostly lined with agate and quartz are cut into small blocks and pieces with flat base to produce desk sets, clock faces and paperweights. Geodes used to make those economical products are abundant in nature and contain less striking agate and quartz colors like gray and white. These small geode units are often dyed and polished with vibrant colors to make them more appealing for customers.

Fine grade geodes (rocks lined with amethyst) are cut into different artistic shapes and used with weighted base or stand to be used as items of décor in residential and office spaces.

Beware of Fake Geodes

If you are paying a hefty amount for geodes, then beware. Fake geodes are also available in the collectors market. Highly skilled con artists line actual mineral stones inside pottery structures, which looks very identical to the original geodes.   

Geode Sites in the United States

Lake Superior Agate

Located in the state of Minnesota, this lake is a buildup of agate that fills the cavities of basalt. It has formed in billions of years.  Most of the geodes have eroded mineral linings, however some stones still contain linings of crystalline quartz and agate of orange and red shades due to higher amounts of iron impurities in the lined minerals.

Minerals

Silver: A Gift of Star Explosions

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Silver BarSilver is often overlooked and overshadowed by the yellow glistening of gold. It seems as if this mineral (considered a mineral when in its native form) plays second fiddle to its more precious cousin. However, this doesn’t change many distinctive facts about this shiny metal. In this article, we will try to discuss a different aspect of this valuable and noble mineral.

History of silver

Southeast Europe (present-day Turkey and Greece area) was considered to be the place where silver ore was discovered for the first time. The archaeological findings suggest that the silver mining in this region dates back to 3000 BC. Ancient people even found a way to extract pure silver from its ore — the process is called cupellation. They used to heat the silver ore and blow air through it. Base metals present in silver ore, such as copper and lead, oxidize in the air and get separated from the silver element.

Egyptians also developed the method to separate silver and gold from each other. They mastered the art of getting silver into its most refined state. For them, this lustrous metal was considered ‘white gold’. Like gold, silver was viewed as a valuable metal in all the ancient civilizations. Due to its various suitable properties, high malleability and durability, it had been used to make coins, jewelry and other items of use.

Silver’s inertness led to its mythical stature  

Since silver doesn’t react to air and never does rusts, many people from the prehistoric era believed it had supernatural powers. In modern times, silver has started to get tarnished due to the increased amount of sulfur in the air, thanks to the industrial revolution.

Different uses of silver

It might sound fictional, but the truth is that silver actually forms in star explosions known as supernovae. According to one study published in the journal of Astronomy and Astrophysics, explosions of smaller stars produced silver while the destruction of larger stars produced gold. The relevance of silver hasn’t ended with ancient times. Even in recent history to this day, it has had many uses.

Silver as currency

Like gold, silver also has a rich history of having been used as the first choice of metal used in currency. There are several reasons as to why this metal had always been a better option to make coins.

    • Silver has a very high melting point in comparison to other metals
    • It doesn’t corrode and rust like most of the metals
    • The luster of silver also makes it an attractive option to produce coins and jewelry
    • It is neither abundant as iron and copper, nor is rare and precious as gold

Due to all these reasons, silver was minted into coins in a pre-BC era in the Mediterranean region.

.999 ounces fine silver Liberty coin
This recently minted coin is 1 ounce, .999 fine silver, non-graded.

Silver as a Commodity

Silver is also a significant commodity in the financial market. As a precious metal, it is traded every day throughout the world and according to some experts, the price of silver is about to jump to all-time highs. Indeed, the market price of silver has more than tripled since 2000.

In addition, silver (and gold) are collector’s items, where hobbyists can buy it in many different forms (coins, bars, etc.) from a variety of reputable agencies. They can either purchase the actual metal or have the company secure it in a vault in order to maintain it in certificate form. For collectors, the former is more frequent.

Precious metals come in either ounces or troy ounces. One troy ounce equals 1.09714286 ounces of silver; however, acquiring one ounce with respect to one troy ounce is more uncommon. Regardless, they are usually in the area of .999% pure silver.

The metal can also come in certified form and it is best to obtain these as opposed to just the metal without certification. The reason is that in certified form, it proves that it is real silver, as well as having a verified value to them. The higher the grading, the more the metal will cost in the collectors market. (In the precious metals market, it would be sold at the going price of the coin e.g if it was going to be sold to a jewelry store, it would be purchased via the going market price).

As of the writing of this article, the prices of one ounce of silver is $16.81.

Silver in photography

Before the digital technology of photography and film, silver was the centerpiece of photographic films that was used to capture images. The coating of silver halide, when exposed to light, reacts by producing a latent image that can be further developed into a photograph.

Medical uses of silver

Due to its antibacterial non-toxic properties, silver has been used in ointments, eye drops and dental hygiene products. Even before the recent medical developments, silver foil was used to wrap around wounds in order to save them from bacteria.

Due to the same antibacterial and disinfectant properties, silver is also one of the ingredients of dental cavity fillings.

Silver in electronics

Silver possesses exceptional thermal and electrical properties that make it an important part of many electrical components where operations can’t be performed by cheap metals like copper and silver. For printed electronic boards, a silver paste made by dissolving silver into nitric acid is used to make circuit paths.

Sliver in the automotive industry

Silver has been used to electroplate engine bearings made of steel. Due to its high melting point, it can withstand high temperatures of engine combustion. The silver surface of bearings also acts as a lubricant and reduces friction.

Silver in the chemical industry

Silver is used as a catalyst in the formation of two important chemical products: ethylene oxide and formaldehyde. Ethylene oxide is used in the industry of molded plastics while formaldehyde is used to produce solid plastics and protective coatings.

Uses of silver clearly shows us that this metal has traveled a long journey through the boulevards of history and is still very much relevant in today’s time and age.

New Minerals

Tumbled Stones – Finer Representation of Rocks and Minerals

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Group of Tumbled Stones
Tumbled Stones, also called Polished Stones are a favorite for decorations

Different rough rocks and minerals that are shaped into small, rounded, and brightly polished pieces are called tumbled stones. Tumbler machines are used for this purpose. The machine tumbles stones and minerals until their rough edges and surfaces get smoothed and polished.

Due to their pleasant and sharp appearance, many people are fond of tumbled stones. They are also called by the names of tumbled gems and polished stones.

Natural Resources Suitable for Making Tumbled Stones

Mineral and rocks that are inherently attractive and radiant in their appearances are used to make tumbled stones. Minerals and rocks with Mohs hardness of more than 5 are considered good choices for the making of tumbled stones because they don’t easily get broken. Hard minerals are also easy to polish. There are different naturally occurring materials that can be used to make tumbled stones.

Chalcedony: It is a cryptocrystalline form of silica with a very fine intergrowth of moganite and silica. Agate, jasper, and bloodstone are the types of chalcedony that are used to make tumbled stones.

Quartz: It is another mineral chiefly made of silica. Crystalline quartz such as amethyst rose and citrine quartz is used to make attractive tumbled stones.

Rocks: Different igneous and metamorphic rocks such as granite, basalt, lapis lazuli, and unakite can also be shaped into tumbled stones.

Fossils: Petrified (fossil) wood, silicified coral, and turritella which contain gastropod fossils are also used as substrates for the making of tumbled stones.

Many other minerals can also be used to produce these attractive, lustrous stones.

Preparation of Tumbled Stones

Rock tumbler is the machine used to make these ornamental stones. Rotary machines used in tumblers usually expose the surface of rough minerals and stones with abrasive grit and water. The barrel which contains minerals and stones rotates for a long period of time. The constant exposure of grit helps in abrading off rough points and edges on the surface of stones.

Once the stones get a smooth texture, they are treated with micro-granular silicon carbide that further improves the softness of the surface in order to prepare them for polishing.  

The final step is to treat the stone with micron-size aluminum oxide. It produces a lustrous and bright surface of the rock to give them the ultimate look of tumbling stones.

Rock Tumbling: A Hobby

People have a hobby of making tumble stones on their own. They collect rough minerals and rocks that can be tumbled into stones. Smaller rock tumbling machines are available that usually tumble a few ounces of rocks into tumbled stones. On the other hand, commercial tumbling machines can work on a few tons of rock at a time.

Traditional Uses of Tumbled Stones

Tumbled stones are used in a variety of ways. Their prices vary according to their weight and the type of mineral and stone that has been used in their making.

For Different Craftworks

Due to their attractive and lustrous appearance and availability in different colors, tumbled stones can be used for a plethora of craft assignments and items.

A Component of many Wearable Arts

Since they look good and are easily available in smaller sizes, tumbled stones are also used in the making of earrings, charms, pendants, cufflinks and tie tacks. Jewelry made of tumbled stones is also reasonable with its pricing.

Standalone Gifts

Larger tumbled stones with stunning appearances can be used as gift items. They can also be used to decorate the wrapping of gift packages.

For Home Décor

To provide a color-coordinated touch to candle holders, picture frames and other home décor fixtures, tumbled stones can be used brilliantly, without spending hefty amounts of money on decorations. They can also be used to fill flower vases with matching colors for further beautification.

A Tool of Alternative Medicine

A large chunk of commercially produced tumbled stones are used for alternative treatment methods in spas, massage centers, and alternative medicine facilities. They are used as healing crystals, chakra stones, and energy stones in alternative medicines.

For instance, there is an alternative concept of having different spiritual points on the body known as chakras.  Tumbled stones are then used to place on these points to relieve physical and spiritual discomforts. These treatments are not endorsed by scientific research, but they are used by many since they possess no harmful side effects.

Classifications

A Fascinating Legend of Alchemy

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Alchemy was supposed to be the predecessor of modern day of chemistry. It has held an important place in medieval times. The subject majorly focused on the transmutation of matter, especially on the conversion of different base metals such as copper, tin, nickel and lead into silver and gold.

The Philosopher’s Stone, has now become limited to the fantasy and fictional work of art. In fact most people, especially generation Y, relate it to J.K Rowling’s book, Harry Potter. It was once the most sought-after substance in the field of alchemy for nearly 1000 years and was used to turn ordinary metals into gold.

Origination of the concept

The concept of the Philosopher’s Stone seemingly has its roots in the theories presented by Geber, a prominent alchemist in the 8th century. He proposed that each element can be categorized by four essential qualities of coldness, hotness, moistness and dryness. This hypothesis became the foundation of the concept of transmutation of metals where one metal can be transformed into another by rearranging these four basic qualities of an element.

The concept of stone turning inexpensive metals into pricey  gold sounded so fascinating that it attracted the attention of influential people who then heavily invested in the search of the Philosopher’s Stone. There was a fine example from medieval times when a Bohemian king, who was facing several financial difficulties, decided to invest in search of the Philosopher’s Stone. A large number of alchemists flocked to Prague, who were provided with sufficient material and financial support, to find out the origin of the Philosopher’s Stone.

What does the Philosopher’s Stone look like?

Since there is no definite trail of the Philosopher’s Stone provided by history, therefore different historical anecdotes tell us different stories. It was called ‘the powder’, ‘the tincture’ or a ‘materia prima’. Materia prima was considered a prehistoric amorphous substance as the original source material of the universe.

The authenticity of the Philosopher’s Stone

The authenticity of this stone or substance is still draped in the cloak of secrecy and mystery. No one can definitely say that there exists a substance capable of transforming cheap metals into gold. However, there are a few intriguing facts that make the history of the Philosopher’s Stone more interesting.

In the 14th century, Nicolas Flamel, a French bookseller and public officer claimed to turn lead into gold with the help of a Spanish scholar and expert of mystic Hebrew text.  He didn’t disclose his methods publically and we are not certain if there was any truth to the claim. However, no one can deny the fact that at the same point of time, Flamel accumulated considerable amount of wealth and donated most of it to several charities.

Isaac Newton, the man who has given the field of modern sciences many undisputed principles, was also lured by the fascination of alchemy, and the Philosopher’s Stone.

Similar to these examples, there are many other historical figures who quested for the Philosopher’s Stone. The obsession of intelligentsia of those times with the Philosopher’s Stone provides some basis to the fact that it may have existed.

Is it just a metaphor?

Since, the Philosopher’s Stone has been heavily studied under the subject of alchemy, and since alchemy itself was famous for using metaphors and symbolisms to associate physical and chemical phenomena to metaphysical and philosophical ones, the possibility of the Stone also being a metaphor exists.

In this mystic side of alchemy, the Philosopher’s Stone was considered to be a symbol of a person’s inner potential. It was believed that the Stone helped an individual develop a higher state of conscious, insight and perfection – something that gold also symbolizes. Against this backdrop, alchemy fused the concept of transmutation of metals, spiritual enlightenment and rejuvenation of the body with the idea of the Philosopher’s Stone.

The Philosopher’s Stone: Its place in modern history

The quest for the Philosopher’s Stone started to die during the 19th century. However, at the end of the 19th century, with the discovery of radioactivity, it became possible to observe that metals can be transformed into other metals by radioactive decay. Frederick Soddy, an English radiochemist, called this phenomenon the transmutation of metal, a concept that had formed the backbone of alchemy and the Philosopher’s Stone.

The truth about the Philosopher’s Stone remains inconclusive, but its legend continues to live.

Minerals

Talc: the Softest Known Mineral

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Talc Mineral
Talc is the softest mineral on earth

Most of us are introduced to the mineral talc through ‘talcum powder’. This powder is the crushed form of talc, which is used to absorb moisture, oil, and odor. It also has contraction effects on the human skin. Due to all these properties, talcum powder has become an important constituent of baby powders, first aid powders, and a range of other cosmetic products.

However, talc is not just limited to making talcum powder and other cosmetic products. There are many other uses of this mineral, which will be discussed in this article.

Talc: a composition of magnesium and silicon

Talc is made of two different minerals with water trapped in their structure. Chemically, talc is called magnesium silicate hydroxide. Usually, talc remains close to this composition, however, sometimes minor amounts of iron, aluminum, calcium, and manganese can be part of talc in place of magnesium. If large amounts of iron substitute magnesium, then talc is transformed into another mineral called minnesotaite, and if this substitute is aluminum then the transformed mineral is called pyrophyllite.

Naturally occurring talc is usually found colorless with a pearly sheen. Talc with green, gray, and brown tinges are also mined. It is one of the softest minerals known and has been given a hardness measure of 1 on the Mohs Hardness scale.

Why talc is soft?

Other minerals such as limestone can also take the shape of powder, but their touch is not as soft as talc. Indeed there is no other mineral in its amorphous form that can replicate the texture of talc. The softness of talc is credited to its physical and chemical properties. Talc is composed of sheet structures with perfect bond cleavages and very weak bond forces between the sheets. Due to these structural traits, talc sheets can easily slip on one another. This characteristic of talc gives it extreme softness.

How talc is formed beneath the Earth

Talc is usually found in metamorphic rocks. Two geological processes form talc in the earth’s crust.

  • When water carrying the deposits of magnesium and silicon reacts with dolomite stones under extreme temperatures
  • When igneous rocks such as serpentinite and dunite undergo alteration due to high temperature in the presence of chemically reactive fluids

The mining of talc

Drilling, blasting, and crushing of the rocks usually highlight the mining process of talc. Extraction of higher-grade ores of talc is carried out through selective mining. To avoid the mixing of other rock minerals in talc, the mining process is done with great care. The contamination of talc can change its color and most importantly, the level of softness for which it is required in many industries.

Crushed rocks from mines are further reduced to particle size and then treated to remove impurities. Froth floatation is usually used to extract the purest form of talc from its ore.

Apart from the cosmetic industry, there is a range of uses of talc in different manufacturing processes due to its different properties.

Talc in ceramic products

Talc is widely used in the making of different ceramic products such as tiles, bathroom and kitchen fixtures, dinnerware, and other pottery items. Due to its high-temperature resistance, it is used as a filler in ceramic, which enhances the firing ability of greenware (unfired pottery) resulting in durable quality products.

Talc in the plastic industry

Many polymer products such as polypropylene, polyethylene, nylon, and polyester get their stiffness reinforced with the inclusion of talc particles. The addition of talc in plastic products also reduces their temperature vulnerability.

There is another reason why plastic industries prefer talc over other mineral fillers. During the process of extrusion, talc’s very low hardness produces less equipment abrasion as compared to other harder mineral fillers.

Talc in the making of paper

Talc is also used in paper production. As we know paper is made from different organic pulps, which are then mixed with talc fillers. The presence of talc in the mixture provides paper with the following characteristics.

  • Smoother surface
  • Increased opacity and whiteness
  • Improves ink absorption

Talc is also used in roofing material to increase its weather-resistant quality. The paint industry also uses talc to improve the suspension of liquid paint.