Category Archives: Minerals

Labradorite: A Feldspar with a Distinctive Optical Characteristic

Labradorite belongs to a large group of silicate minerals, believed to make up more than half of the Earth’s crust, known by the name of feldspar. Labradorites are usually found in the igneous rock formations all around the world. Before discussing the wonderful optical characteristics associated with this stone, let’s delve into some of the details about its geographical occurrence.

Presence of Labradorite in the Nature

Labradorite can be found in different unique geographical settings. They are mostly formed through the process of metamorphism in which igneous rock of norite and basalt transforms into foliated rock formations. But they can also be found in sedimentary rock specimens that break away from the geological formations containing labradorites due to extreme environmental conditions.

Labradorescence:  Exhibition of Schiller Effect From This Feldspar Specimen

Some of the labradorite specimens have the inherent ability to exhibit rare optical phenomenon of adularescence which is commonly known as Schiller effect. In this optical exhibition, stones glow with a sheen which is coming from the inside of the stone instead of its surface. Opal, agate and moonstone are the widely known gemstone or ornamental specimens which possess the property of adularescence.

However, this same phenomenon becomes very different altogether, and in a good sense, when it is observed in some of the labradorite stones. Because few specimens are so good with the Schiller effect that they simultaneously exhibit multiple colors from the inner layers of their structure. Due to this distinctive and strong demonstration of adularescence, this phenomenon has got its own name as “labradorescence”.

How Labradorescence occur?

We have already known that how adularescence works. Labradorescence also plays in the same way where light reflects back from the internal surfaces instead of the exterior of the stone but here more than one type of wavelengths are reflected back by the internal twinning layers of the stone which are seen in the form of different colors ( blue, orange, red, green) by the observers. Labradorites possess adularescence or labradorescence are considered gem-grade feldspar.

Famous Labradorite Mining Locations

There are geographical locations all around the world which are famous for the deposits of labradorite.

Labrador, Canada: Birthplace of Labradorite

These unique feldspar stones were discovered in the 17th century on the Isle of Paul, Labrador, Canada and hence named after the place which is a province of present day Canada.

Gray and Black Labradorite: Russia and Madagascar

Gray and black labradorites which exhibit fine labradorescence can be found in Russia and Madagascar. It is interesting to note that both of the countries are more than 6000 miles apart but still host the same variants of labradorites.

Spectacular Deposits in Finland

Labradorites with an exceptional exhibition of labradorescence are mined from rare deposits of feldspar in Finland. They even named by the local administration “spectrolite” because of their spectacular display of rare optical characteristics.  

Oregon Sunstone: A National Labradorite Deposit

Labradorites are also mined in the US. However, they don’t possess the characteristics of labradorescence. Feldspar mines in the state of Oregon produces these stones different hues with a more transparent crystalline structure.

Labradorites mined in these sites are branded with the name of ‘Oregon sunstone’ and there is a reason to that. Many of the stone specimens found in this area contain metallic inclusions in the form of copper impurities. Due to this, these labradorites get the property of flashing with aventurescence in the presence of light. This specific property of Oregon labradorites compensates the absence of labradorescence. It is in great demand due to its popularity among local jewelry dealers and tourists.   

Labradorite: As a Gemstone and Décor Material

Labradorites with strong exhibition of Schiller effect are usually cut into gem-grade sizes of stones. They have a Mohs Hardness of around 6, making them more suitable for jewelry items that are less exposed to abrasion. To cherish the labradorescence of the stones, they are cut into cabochons. These cabochons are cut in a way where their base is corresponding to the inner twinning layers producing adularescence flashes.

Some large specimens of the stone can be cut into slabs which then can be employed in the making of small sculptures and other decor articles.

How to Distinguish Real Emeralds and Ambers from the Fake Ones

Gemstones are beautiful and precious and have been used in the fields of astrology, medicine and fashion for thousands of years. With time and technological innovations, fake or synthetic gemstones have also made their way into the gem market. If you are spending significant money on buying gems, make sure that you are getting the ones that are real, as the chances of getting conned are very real as well.

In this article, we discuss some of the techniques and methods that you can use at home to distinguish between real and fake emeralds and ambers. As the commercial says “The more you know…”.

How to identify a fake emerald

These green beauties are one of the most prized and beautiful gemstones out there. They can be used as ornaments in any style of jewelry, be it a bracelet, necklace or earrings. Emeralds are relatively harder than other gemstones, but real emeralds are not as hard as synthetic ones. Natural emeralds contain internal imperfections, which make them easier to break, compared to synthetic ones that are manmade and free of imperfections.

What are fake emeralds?

Fake emeralds are usually categorized into two categories

‘Natural’ fake emeralds: Since emeralds belong to the beryl family that is green, natural gemstones of the same color shade are often also sold off as emeralds. Peridot, olivine and green garnet are usually sold in the name of emeralds.

Synthetic emeralds: Synthetic emeralds that are created in the lab possess the same internal crystal lattice as natural emeralds, so in theory, they are not fakes. If you are going to buy a synthetic emerald then make sure that it is priced less than the natural ones.

A simple way to tell whether a stone is synthetic or natural is to observe its surface texture. Synthetic emeralds appear cleaner than natural emeralds since they don’t possess any natural impurity.

Some other techniques which can help you find out the genuineness of an emerald:

Check hues and reflection

A natural emerald usually doesn’t possess non-green hues. The secondary undertone of any color other than green indicates that the emerald is a fake. Another way to check is to expose it to light. If the stone exhibits colorful reflections, it is probably bogus. Real emeralds don’t reflect strong flashes.

Clarity can tell the authenticity of an emerald

Remember a general rule, the clearer the stone looks, the greater the chances that it is fake. You can use a normal magnifying glass to check the clarity of the stone. In natural emeralds, you will observe bubbles and crystal formations inside the stone, while synthetic ones don’t possess such imperfections.

How to identify fake Ambers?

Falling in the color range between gold and orange, this gem made of a fossilized tree resin has been appreciated by human beings since the Stone Age. It is imperative to know the difference between real and fake ambers because real ambers are used for different purposes.

  • They are used as decorative objects and in jewelry
  • Since they are a tree resin, real ambers are also used as ingredients in perfumes and scents
  • Many people use amber for its range of healing properties

Buoyancy test

If you want to test the beads of amber for their originality, then you can conduct a salt solution test. Put the amber stones in a supersaturated salt solution. Real ambers will not sink, while the fake ones will touch the bottom.

Scratch Test

Remember that not all ambers are same in their price. Ambers that are used for health benefits are cheaper than the ones that are used in jewelry. Only inexpensive amber can be subjected to this test. Just scratch the surface of the amber with any metallic object using soft hands. Fake ambers (usually made of glass) won’t get any scratches on their surfaces.

Electrostatic test

There is another tree resin by the name of copal, which is also sold as amber because its surface texture is almost identical to real amber. To know whether you are holding amber or a copal, you can simply perform an electrostatic test on the stone to find its authenticity.

When rubbed continuously for a minute, real amber produces an electrostatic field around it. You can test this using a tiny piece of paper or a strand of hair. If paper pieces or hair strands stick to the stone, it means that there is an electrostatic field presentand that the stone is real.

Enigma of Diamonds: Expensive Yet Always in Demand

Fine Cut DiamondThey are the manifestation of glitz.  Some refer to them as the tears of the gods and some consider them stardust. No matter how you identify with them, diamonds have captured the imagination of mankind since the very beginning. And the real wonder is that even after all these years, human beings are still dazzled and mesmerized by the enigmatic beauty of these precious stones.

In this article, we will find out what factors make this beloved gem so expensive and how it has been part of the human history for so long, so let’s begin with some relatively less known facts about diamonds.

Not all diamonds are expensive

Very few people are aware of the fact that not all types of diamonds are as expensive as we are taught to believe. Diamonds don’t come out of mines in the shape and texture we are used to seeing in ornaments and jewelry items. In fact, most of the natural diamonds never make it to that beautiful refined state because they come with too many imperfections and defects and consequently, such diamonds are only really suitable for industrial use.

Since the majority of mined diamonds can’t be used in jewelry, we are left with very few grades of diamond that have such quality, the expensive ones that can be used for decorative purposes.

It’s the simple imbalance of supply and demand makes this stone expensive. But that’s not all. There are other characteristics which add to the cost of diamonds.

Color of the Stone

The diamond’s color is one major factor in determining its price. Most of the naturally occurring diamonds contain a noticeable tinge of a yellowish hue. In fact, it is hard to find a stone that is completely colorless; thus, the more colorless a diamond is, the rarer and more valuable it is.  Although they may be colorless, the diamonds will appear whiter and brighter to the eye. Therefore these diamonds automatically become more expensive.

When traces of the yellowish hue drop, the demand and price of the diamond increases exponentially. This is more noticeable for diamonds that have other color traces like pink and blue in them. These color traces come from the natural impurities that are present in the internal chemical structure of the stone but are valued highly by diamond lovers.

Clarity of the stone

It is very rare that an original diamond comes without any internal spots and lines within the stone. Now, you can easily deduce how difficult it is to find the stone that has the color shade of your choice and comes with the clarity you want. Once again, demand and supply sets the price of the stone.

Size of the stone

The weight and size of the diamond also affect its price. Diamonds that are larger in size are hard to find naturally and consequently come with an expensive price tag.

Cut of the stone

As we all know, mined diamonds can’t be fitted directly onto jewelry. They have to be polished and cut into a shape that can give optimal balance between size, clarity and color. Getting the perfect cut is a tricky prospect.

There is a tremendous balancing act involved in which the cut has to be made to enhance clarity without reducing the weight of the stone. There is always the chance that the weight and size of a diamond may be compromised while removing some visible imperfections from it.

As a result, a diamond with balanced aspects of clarity, size and shape are hard to find and expensive to buy.

Have diamonds always been so popular and in demand?

Diamonds have not come to the forefront from the renaissance, agricultural or industrial revolution. They have been important since ancient times when the Greeks ruled the world. Even the name ‘diamond’ is said to be derived from the Greek word ‘adamas’, meaning indestructible, because the Greeks associated the radiant and ever-glowing glitter of the diamond to be an indestructible sign of love.

Generally, throughout the course of history and various civilizations, diamonds have always been considered as the sign of supreme power. Many cultural dogmas considered diamonds to contain magical powers that can be used to cure madness and repel evil spirits. Plato, the famous Greek philosopher shared the thought that diamonds were living spirits. Diamond powder, due to its curing abilities, had also been used in medicines.

There are a lot more historical anecdotes that can be mentioned to highlight the fact that the diamond has always been popular. It’s this popularity that makes it so expensive.

 

Opal: A Precious Stone with a World of Colors

Coobe Pedy Opal Doublet Mineral
Coober Pedy Opal Doublet Mineral

Due to its exuberant display of color, opal has often been compared with erupting volcanoes, galaxies and fireworks. A stone exhibiting such grandeur inherently appears mystic and mysterious. And we humans  are always intrigued and fascinated by such characteristics. Therefore, opal comes in an elite category of stones that have always been appreciated and revered the world over.

What is an Opal?

The opal stone is classified as mineraloid, a mineral-like substance that doesn’t possess the characteristics of crystalline structures. Opal is an amorphous form of silica which displays a mix of various colors giving it its enhanced enchantment quality. The colors are borne out of the chemical and physical conditions in which the stone is formed.

Most common opals have green and white hues, while black opals are considered to be the rarest. Let’s look into the history of opal to know how this gemstone has been perceived over time.

Historical Journey of the Opal

Opal became mainstream with its discovery in South Australia in the 18th century. However, anthropology tells us that opals were in use way before this discovery.

An opal artifact was discovered from a cave in Kenya which dates back to 4000 B.C. According to anthropologists, these artifacts were brought over from Ethiopia.

Apart from that, opal is also depicted in many ancient paintings as a part of ornaments and jewelry. In ancient Europe, Hungary was the origin of opal mining and it is believed that Spanish soldiers introduced this stone to the rest of the world in the 16th century.

Name’s Origin

The historical significance of opal can also be authenticated by the origin of the name ‘Opal’.

  • According to some references, the name opal is derived from a Sanskrit word ‘Upala’ which means ‘precious stone’.
  • Many historians associate the word opal with ancient Rome where two languages were dominant, Latin and Greek. A Latin word ‘Opalus’ means ‘precious stone’ is also thought of as the origin of the name, while the Greek word ‘Opallios’ meaning ‘to see a color change’ is also considered to be a strong contender for the origin of the word Opal.

It is quite evident that whichever origin story you want to buy, the characteristics of opal have always been linked to magnificence.

Types of Opal

Opal is categorized into different types according to its optical density and colors. There are numerous types of opals according to their appearance, however we will discuss the ones that are found commonly and are more popular among all the different types.

Fire Opal: They are mostly mined from Western Australia and contain the background color combination of yellow and red with an overall semi-transparent appearance.

Black Opal: Opals are called black due to less transparency which makes their appearance darker. Black opal exhibits beautiful play of color which makes them one of the most attractive and popular opals out there.

Boulder Opal: This type of opal is basically housed in the fractures of a stone in the form of vein like meshwork. These opals are mostly mined along with their host stone so that the opal remains in its natural state.

Common Opal: Common opals have the highest opacity and does not exhibit any play of color. However, common opals can be used in ornaments due to their lustrous appearance.

Gem Therapy with Opal

Gem therapy has been practiced in a plethora of cultures around the world. Although, not scientifically proven, anecdotal evidence  suggests that gems do have healing powers. With that said, some health benefits that might be associated with opal are:

  • Fire opal is thought of having healing power for blood related diseases. Its psychological benefits include getting rid of laziness and depression.
  • Black opal has therapeutic benefits for reproductive disorders. By wearing black opal people can also get rid of the stress that comes with those reproductive disorders.
  • White opals are considered very effective for people who have been experiencing neurological disorders.
  • People who are facing sleeping disorders and have frequent nightmares can wear almost any kind of opal stone. Opal is known to relax and therefore, help you sleep.

Zodiac Association of Opal

Opal is considered as the gemstone for the month of October in the Gregorian calendar. It is said to be a suitable gemstone for all those zodiac signs that are ruled by Mercury. People with zodiac signs of Cancer, Libra, Pisces and Scorpio might want to wear opal for its potential benefits.

Zircon: From Gemstone to Pigment

Zircon gem in red

Photo by simplyyayimages.com

Zircon is a mineral compound composed of the elements zirconium and silicon. Zircon is commonly found in nearly every type of rock formations all around the world. Zircon has been used as a gemstone for millennia. Even though zircon comes in different colors but the most sought after is colorless zircon due to its close resemblance with diamonds, thanks to its fine dispersion and brightness.

Name and history of zircon

Zircon faces chronological injustice because most of the people know it as an imitation element due it its extensive use as a low-cost diamond substitute in the beginning of the 20th century. However, the stone is naturally found in many different shades. Even the origination of the name ‘zircon’ indicates that the other colors of the mineral were equally popular in the past.

Name origin of zircon

There are two popular theories regarding the name origination of this mineral stone:

  • Some historians think that ‘zircon’ is derived from the Arabic word ‘zarkun’ which translates to vermilion or cinnabar, both represents the different shades of red.
  • Other historians are of the thought that zircon is borrowed from the Persian word ‘zargun’ meaning gold colored.

With zircon’s natural occurrence in a wide variety of color shades, either of the name origination can be true.

A prized stone during medieval times

Different variants of zircons held important place during middle ages. People believed that these stone had the ability to repel evil spirits. Possessing zircon was associated with good fortunes and wisdom.  

Important ornamental stone of Victorian era

Zircon became widely popular during Victorian era. Many jewelry specimen of the time were fitted with rare blue variants of the gemstone. A famous gemologist of the time, George Kunz was known for his fondness of zircon. He even proposed the change in name of the stone to highlight its vivid characteristic.

Geology of the stone

Igneous rock formations that have undergone the process of metamorphism usually host zircon gemstone. They are also found as accessory mineral in granite deposits. Most of this zircon goes unnoticed because its aggregate are present in very small size dispersed in a larger volume of the given ore.  

Gem-grade variety of zircon can be found in the soil and sedimentary rocks. Due to their high resistance to graze and chemical reactions, they remain keep their shape and structure even when the rock formation around them undergo erosion. Therefore, there are certain billion-year old deposits of zircon as per their carbon dating. The bigger the cut of zircon, the better it would be to be used as gemstone.

Gemstone zircon

Even in modern times, zircon gemstones are used in many jewelry items. Most of the famous choices of zircon gemstone are brown, red and yellow and treated variants of green and blue. We have already discussed that colorless zircons are used as the low cost diamond substitutes. The other in-demand type of modern times is blue zircon.  

Perfect fit for jewelries’

Due to its greater value of hardness on Mohs scale (7.5) and good cleavage grading, it is suitable to be used in different ornamental items including earrings, brooches, rings and bracelets. Jewelry items featuring zircon as the primary gemstone can last for many years without losing the sheen and magnificence of the stone.

Industrial and gem-grade mining of the stone

Since the use of zircon is not limited to the domain of jewelry and gems anymore. Industrial use of zircon has also been established with time. Mining of both type of grades are usually done in separate geological sites.  

Gem-grade

Gem-grade deposits of zircon are being mined for centuries from the alluvium deposits located in the far eastern countries of Vietnam, Myanmar and Cambodia. Sri Lanka is also famous for the mining of gem-grade zircon.  

Industrial-grade

Now more mining of the stone is done for the sake of its industrial uses. Australia tops the chart for mining zircon for its industrial uses. Brazil, China and Kenya also have some noteworthy land and marine alluvial deposits of industrial-grade Zircon.

Due to its high temperature resistant characteristic, zircon is used as a refractory lining that are installed inside furnace and kilns. By converting zircon mineral into zirconium dioxide at extremely high temperature, it gets into amorphous form which is then used as a pigment in different industrial and manufacturing processes.  

Ammolite: A Marine Fossil Gemstone

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 determines 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 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 are done as per 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

Ammolites found in the fossil sediments of Gandaki River in Nepal usually show golden luminescence and has 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 recommends 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.

Extraterrestrial Gemstones

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 few interesting facts about them:

  • Sometime, meteorites contain more than two metals, like an alloy. They can be used as extraterrestrial ornaments and gems. For instance, alloy meteorite 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 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 of such gemstones and even that are 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 on 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 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 collectables.

There are some famous ET gemstones and rocks that have captured human imagination and have 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 meteor impact in the area. The glass is created from the silica abundantly found in the desert sand.

There are few sites all over the world where desert glass can be found. Most popular subtype of this of 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 pre-BC era shows that desert glass has been used by humans for thousands of years. King Tutankhamen, 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 from the Tomb of the Egyptian king has desert glass as its center piece.

Popular for Metaphysical Properties

Even now, desert glass is used for its metaphysical properties. It is thought to have 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 will power of the any living body.

Moldavite

Moldavite are formed due to a meteorite impacts in southern Germany. They are dull green fragments of meteorites that are considered gem-grade stones. In alternative medicine, moldavite are very popular due to their healing powers of 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.  

 

Lapis Lazuli – a Heavenly Blue Rock Gemstone

Lapis Lazuli Stones
Photo by richpavyayimages.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.

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.