Corundum – Parent Mineral of Ruby and Sapphire

Corundum Mineral Stone
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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.

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 ruby gemstone.

Occurrence of corundum in the 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.

Lapis Lazuli – a Heavenly Blue Rock Gemstone

Lapis Lazuli Stones
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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.

Topaz: A Mineral Made of Silica and Fluorine

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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.

Geodes – A Natural Pouch of Stunning Minerals

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.

Silver: A Gift of Star Explosions

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 shinny 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 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 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 metals
  • The luster of silver also makes it an attractive option to produce coins and jewerly
  • 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 pre-BC era in the Mediterranean region.

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

Silver as a Commodity

Silver is also a valuable 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 collectors 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.

Tumbled Stones – Finer Representation of Rocks and Minerals

Tumbled Stones Variations
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 the 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 tumble stones. Minerals and rocks with Mohs hardness 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 are 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 stone.

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 rotate 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 Craft Works

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.

A Fascinating Legend of Alchemy

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.

Talc: the Softest Known Mineral

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 due 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 substitutes 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 the hardness measure of 1 on the Mohs Hardness scale.

Why talc is soft?

There are other minerals such as limestone that 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. There are two geological processes that 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 of 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 due to which 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 that 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.


Blue Flames and Acid Lake: A Geological Marvel Around Indonesia’s Kawah Ijen Volcano

Kawah Ijen Volcano, Indonesia
A geological marvel of blue sulfur gases at the  Kawah Ijen,volcano in Indonesia

The volcano of Kawah Ijen, situated on the island of Java, is known for two distinctive geological phenomena. It is a shallow volcanic crater emitting hot and combustible sulfurous gases. These gases burst into electric blue flames when they enter Earth’s atmosphere due to the abundance of oxygen. A portion of the emitting gases also get condensed in the atmosphere to take the shape of molten sulfur. The blue ambiance created by burning sulfur produces a striking view, especially at night.

The second geological phenomenon is a one kilometer wide caldera lake of turquoise blue water. This unusual color of water is due to high acidity and high concentration of dissolved metals in the reservoir.

This caldera reservoir is the most acidic lake with a measure pH of as low as 0.3. These high levels of acidity are caused due to the fact that hydrothermal waters inflowing in the lake is charged with gases from a hot magma chamber.

History of the Volcano

According to geological findings, volcanic activity in the area began 300,000 years ago with the buildup of a humongous stratovolcano which is now known as Old Ijen. A stratovolcano is a high, conical buildup of layers of hardened lava and volcanic ash. The volcano grew to the height of about 1000 feet over thousands of years with repeated eruptions.

The caldera lake was formed about 50,000 years ago with a cascade of intense volcanic eruption. During last 50000 years, many small stratovolcanoes within this Caldera including Kawah Ijen have been formed. Kawah Ijen is located in the eastern part of the Caldera.

The volcano is still active, but hasn’t experienced magmatic eruptions since 1817. However phreatic eruptions have been happening till today. The last phreatic activity occurred as recently as 2011.

Lake Also Produces Sulfur Deposits

The opening of volcano at the lake-side produces a continuous stream of sulfur enriched gases. These gases usually flow underground in the absence of oxygen. If the gas is hot enough at the time of eruption, then sulfur will ignite into blue flames, but usually the temperature of the mixture is not that high, which results in the condensation of molten sulfur when it comes out on the surface. This molten sulfur then travels a short distance before ending up in solidified form.  Local people collect those deposits of sulfur and sell them to a local sugar refinery.

Kawah Ijen Volcano: One of the Few Sites of Artisanal Mining in the World

Most of the sulfur produced around the world is the byproduct of natural gas processing and oil refining. This site is one of the few ones where sulfur was mined, even though the process is a dangerous one. Miners have to walk up to the top of the mountain and then descend down the dangerously steep and rocky paths of the crater. They use metal objects; usually steel bars to break solidified sulfur from the outcrops. They fill up their baskets with soft sulfur rocks travel back to the sugar refinery. Miners are paid according to the weight of the sulfur.

Recently, miners have installed numerous pipes along the mountain. This network of pipes is created to collect the sulfur-laden gases from various vents and openings of the volcano and direct them to those areas from where gathering sulfur deposits is easy. This development has made the process of collection more efficient and less harmful for the miners.  

Kawah Ijen Volcano: A Tourist Site

Many adventurous people have made this place a tourist site. The area around possesses a beautiful landscape with fauna that can only flourish in these highlands. With an elevation of more than 2,000 meters, atmospheric temperature around the volcano is usually low. The fusion of different air temperatures — cold ambient air merging with the heat escaping from the volcanic openings, creates a very peculiar sensation that can’t be felt anywhere else.

A moderate 3-km track, which traverses through Casuarinas forest, leads up to the volcanic rim. From here the journey gets arduous with 2 km more of relatively steep trail and ends up giving you a breathtaking panoramic view of Ijen Caldera. A slightly pungent smell of sulfur fumes rising from the acid lake will welcome you. For safety purposes, it is better to wear a gas mask.


Infinity stones: Gemstones of Marvel’s Fantasy Universe

We humans have been fascinated by the gemstones since time immemorial. From millennia, before branching into different civilizations, we had become fond of the rare stones that look different from the regular ones.

This obsession with gems doesn’t stop here and we have incorporated them into literature and art well. From the fantasy world of Star Wars to the universe of Marvel comics, ‘gemstones’ have important part in the story lines. In this article, we will try to look how Marvel Comic strips incorporate the fascination of gemstones on its vast canvas of stories.

The six infinity stones of Marvel Universe

Many of us have heard a about infinity stones in the marvel cinematic universe. But before that they were called soul gems. All of these fantasy gems, in their color and texture, resemble the real-world gems.

There were total infinity or soul gems in Marvel’s universe and according to the present day timeline all of them are in different places. However, history of this universe tells us that these infinity gems possess infinite and unparalleled powers and that is why they even become the bone of contention among different powerful entities of the universe.

The power of infinity stones can be gauged by two different anecdotes from the comic strip:

  • Thanos, one of the super villains of Marvel Universe tired to use all the six gems in unison to destroy the stars but Avengers stopped him from using the power of infinity gems.
  • Elders of the universe, the oldest and survivor of their respective species used the combined energy of the stones to energize the barren planets.

Let’s look into the qualities and capabilities of each stone that has been important part of Marvel universe since the beginning.

Space gem (Tesseract)

The purple soul stone inspired by the color of real earth gem of amethyst is famous for its teleportation capabilities. Its blue rays are teleporting objects from one place of the other throughout the universe. It is also able to interfere in the movement of moving objects. Another use of space gem apparently is being used as a part of advanced weapon systems.

You can see this stone in the movie Captain America being used by Red Skull and in The Avengers by Loki.

Reality gem (Aether)

This gem yellow in its color is used to alter the reality, logic and bend the law of physics. The stone has a range of different wonders that are differs in their scale. The stone can be used to resurrect the dead. It can be used to distort and change the reality around any individual.

If used with more power, it can used to create the whole new desired reality. Its power gets exponentially high when it is used with other infinity stones and then it can alter the reality on a universal level. It is inspired by citrine and yellow sapphire.

Mind gem

It was lastly seen in the hands of Loki. This blue stone sapphire-like gem has infinite psychic abilities like telepathy, empathy and moving physical objects with the sheer mind power. When used with other infinity stones, it can connect the user’s mind with all the other minds of the universe in the same moment of time.

Power gem

Seen as the reddish ruby-like stone in the comic stripes, this infinity stone can grant all the power to its possessor that has ever exist or will exist in the universe. It increases the strength and stamina of any human to superman levels. The stone also helps other stones to produce their own powers and energy.

Soul gem

As the name suggests, it can be used to observe, attack or control the soul of any living being. It also protects the user with external magic attacks on his soul. Soul stone can also be used to revert back the mutated beings to their natural state. Soul gem resembles the real word emerald.

Time gem

Resembles with garnet or coral, this infinity stone is capable of playing with time as a physical object. It can stop, slow, speed up the time flow. Wielder of this stone can time travel and can see through the past and future. It can also used to alter the aging process.

The popularity of Marvel’s comic has a significant contribution from these fictional infinity stones and all them are inspired by one or the other real gems.

Howard Fensterman Minerals