Gemstones

Amber
Amber is fossilized tree resin. It is organic not mineral. The oldest amber dates to the Upper Carboniferous Period, about 320 million years ago.

An ant inside Baltic amber
Scientists and collectors treasure amber that contains suspended animal or plant fragments. These fossilized parts of once-living things were trapped in the hardening amber, creating a time capsule.

Amber's warm luster is featured in beads, carvings, pendants, cabochons, as well as decorative items. Transparent amber is more valuable than cloudy. A plant or animal inclusion adds greatly to the value of an amber specimen.
Peter the Great’s Amber Room near St Petersburg was made from six tons of amber. A Prussian gift in 1716, It was lost during WW II, but recreated in 2003.

The word amber means brownish yellow, but the gem can be yellow, golden, white, orange to reddish brown, or even bluish or greenish.
Cutting and polishing amber for jewelry makes it more susceptible to oxidation by removing or thinning the harder exterior surface. Fine translucent yellow or orange amber can gradually darken to reddish brown and eventually black.
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Beryl

Emerald with Pyrite, Calcite
In geology, beryl is a mineral composed of beryllium aluminium cyclosilicate with the chemical formula Be3Al2(SiO3). Beryls come in a number of varieties including the blue-green aquamarine, yellow-green heliodor, pink morganite, deep green emerald and the extremely rare red beryl.

The name comes from the ancient Greek word beryllos describing a blue-green stone the color of the sea.
Emeralds are a form of beryl, showing the richest green which is caused by trace amounts of chromium and sometimes vanadium. Emerald has been a favorite of the elite throughout history. Its attributes include the ability to foretell the future, bring good luck and protect against illness.

Emeralds in antiquity were mined by the Egyptians and in Austria, as well as Swat in northern Pakistan. A rare type of emerald known as a trapiche emerald is occasionally found in the mines of Colombia. A trapiche emerald exhibits a "star" pattern. It is named for the trapiche, a grinding wheel used to process sugarcane in the region. Colombian emeralds are generally the most prized.

Golden beryl can range in colors from pale yellow to a brilliant gold. Unlike emerald, golden beryl has very few flaws. The term "golden beryl" is sometimes synonymous with heliodor.

Both golden beryl and heliodor are used as gems.
Morganite, also known as "pink beryl", "rose beryl", "pink emerald", and "cesian (or caesian) beryl", is a rare light pink to rose-colored gem-quality variety of beryl. Orange/yellow varieties of morganite can also be found, and color banding is common.

Pink beryl was first discovered on an island on the coast of Madagascar in 1910. In December 1910, the New York Academy of Sciences named the pink variety of beryl "morganite" after financier J. P. Morgan.
Red beryl (also known as "red emerald") is a red variety of beryl. It was first described in 1904 for an occurrence at Juab County, Utah.

Red beryl is extremely rare and has only been reported from a handful of locations. The greatest concentration of gem-grade red beryl comes from the Violet Claim in the Wah Wah Mountains of mid-western Utah, discovered in 1958. While gem beryls are ordinarily found in pegmatites and certain metamorphic stones, red beryl occurs in topaz-bearing rhyolites. It is formed by crystallizing under low pressure and high temperature from miarolitic cavities of the rhyolite.
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Black Opal
In the first century A.D. Pliny wrote of the opal, "for in them you shall see the living fire of the ruby, the glorious purple of the amethyst, the sea green of the emerald, all glittering together in an incredible mixture of light", and later Shakespeare was to describe it as the "Queen of Gems".

Due to its colour play the opal has been subjected to many superstitions and myth. Opal was said to ward off diseases and for this reason was worn in amulets. In Roman times it was included in the crown of the Holy Roman Emperor.
Opal, from the Greek, "Opallos", meaning 'to see a change (of colour)', is a formation of non-crystalline silica gel.

Millions of years ago, the gel seeped into crevices and cracks in the sedimentary strata. Through eons of time and through nature's heating and moulding processes, the gel hardened and can today be found in the form of opals.
Black opal is the rarest and most valuable type. It is generally found as a bar of various colours forming natural water horizontals in dark grey to black "potch nobbies" or "nodules". The unique patterns are as complex as an artist's imagination.

95% of the world's supply of this radiant, dark lustrous gem is mined at only two pinpoints on the globe - Lightning Ridge and Mintabie, Australia.
The world famous black opal field of Lightning Ridge was discovered in 1903 and is still producing gems.

The discovery of light opal in 1915 made famous the name of one of the most hostile and remote places on the Australian continent - Coober Pedy, the largest opal producing centre on earth.
Coober Pedy, an Aboriginal name meaning "White man in a hole", adequately describes the mines and miners' dwellings - burrows dug into the scarp, in order to escape the soaring temperatures of the day and the freezing winds at night.
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Blue Garnet
Garnets are a group of silicate minerals that have been used since the Bronze Age as gemstones and abrasives. All garnets possess similar physical properties and crystal forms, but differ in chemical composition. The different species are pyrope, almandine, spessartine, grossular, uvarovite and andradite.

Garnet is available in a plethora of colours and is found around the world. Rarest and most valuable are blue garnets. They were discovered in 1998 in Bekily, Southern Madagascar. They are actually colour change garnets, appearing blue under fluorescent light changing to reddish-purple under incandescent light. The color change is pronounced and these rare garnets have become highly sought after by collectors.
Color change garnets are due in part to varying concentrations of vanadium and chromium. The blue-green to purple color change garnets have relatively high concentrations of vanadium and low concentrations of chromium.

Very fine, gem quality blue garnets over 10 carats are scarce and valuable.
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Chrome tourmaline
Chrome tourmaline is a special member of the tourmaline group. Found only in east Africa, it is usually found in small sizes. What it lacks in size it makes up for in color - it displays perhaps the richest, most intense green in the gemstone world.
There are similarities between chrome tourmaline and tsavorite garnet. They are found in the same locations in Tanzania, and both are colored by chromium and vanadium. Chrome tourmaline, in many ways, is equal to the finest tsavorite.

Chrome tourmaline is a distinct variety of tourmaline, called chrome dravite.
Like emerald and tsavorite garnet, fine chrome tourmaline is a pure forest green with slightly yellowish to bluish secondary hues. With a hardness of 7 to 7.5 on the Mohs scale and no cleavage, tourmalines of all types have good durability.

Generally, tourmalines are Type II clarity stones, showing inclusions. However, one can find eye clean green chrome tourmalines. Most would only buy chrome tourmaline graded IF (internally flawless) to VS (very small inclusions).

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Chrysoberyl - Alexandrite
Chrysoberyl is an aluminate of beryllium with the formula BeAl2O4. Despite the similarity of their names, chrysoberyl and beryl are two completely different gemstones. Chrysoberyl is the third-hardest frequently encountered natural gemstone.

The three main varieties are ordinary yellow-to-green chrysoberyl, cymophane (cat's eye), and alexandrite.
Cymophane exhibits chatoyancy or opalescence that appears very much like an eye of a cat. When cut to cabochon, the mineral forms a silky band of light extending across the surface of the stone.

Microscopic tubelike cavities or needlelike inclusions of rutile are orientated parallel to the c-axis producing the chatoyant effect.

Alexandrite undergoes dramatic shifts in color depending on what kind of light it's in. A variety of Chrysoberyl, alexandrite's color-changing properties is due to an exceedingly rare combination of minerals that includes titanium, iron and chromium. Originally discovered in Russia’s Ural Mountains in the 1830s, it’s now found in Sri Lanka, East Africa, and Brazil.
Fine, gem quality material is exceptionally rare and valuable. Alexandrite's mohs hardness is about 8.5.
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Colour Change Spinel
Spinel is a hard vitreous magnesium aluminum oxide that has been used as a gemstone for centuries. Spinel has been mistaken for ruby and sapphire in the past. Spinel occurs in a range of colors.
Spinel can be distinguished from other gemstones by its octahedral crystal structure and single refraction. Spinel has a lower Mohs hardness than ruby and sapphire. Spinel occurs with ruby and sapphire, and significant deposits have been found in Cambodia, Myanmar (Burma), Sri Lanka (Ceylon) and Thailand.

The rarest and most desirable spinel gemstones are vivid ruby-like red, followed by cobalt blue, bright pink and bright orange. Prices for 'class A' color-change spinel offer excellent value. According to some experts, current prices for color-change spinel are an insult to their beauty and extreme rarity.
See ----->http://highlifelivingluxury.blogspot.ca/2016/11/royal-spinel-balas-ruby.html
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Imperial Topaz
Topaz is a silicate mineral of aluminium and fluorine.

Pure topaz is colorless and transparent but is usually found tinted by impurities; typical topaz is wine, yellow, pale gray, reddish-orange, or blue brown.
There is no official standard for imperial topaz. Some dealers use the term for colours that are orange to pink to red to purple, others reserve the term for certain saturated shades.

It’s the colour, not the term “Imperial” that gives topaz its value. Imperial Topaz, with its distinct peach, pink, orange or champagne hues, is the rarest topaz variety and the most valuable.
The primary source is the Ouro Preto mines of Minas Gerais, Brazil. Deposits were also found in the Urual Mountains in Russia. Imperial topaz was named in honor of the Russian monarchy who prized it. Today imperial topaz is classified as a very rare collector's gem.

The price and value of imperial topaz vary depending on the size and quality of the gemstone. True imperial topaz is always untreated, and material which has been colored by artificial means such as irradiation is not regarded as genuine imperial topaz.
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Indicolite - Blue Tourmaline
Tourmaline occurs in virtually every color, but blue is the rarest. The blue tourmaline that has attracted the most attention recently is the rare paraiba variety that was first discovered in Brazil in 1989, and then in Nigeria and Mozambique. These gems, colored by copper, have a neon-like quality that is highly coveted by collectors.
Indicolite tourmaline, colored by iron, can vary from a light to a deep blue. Like most tourmaline, it is strongly pleochroic, meaning it shows different hues when viewed from different directions. Indicolite which is a pure blue is extremely rare, and most examples will have a green secondary hue.
The main sources of indicolite tourmaline are Brazil, Nigeria, Afghanistan, Mozambique and Madagascar.
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Jadeite
Jadeite is a pyroxene mineral with composition NaAlSi2O6. It is monoclinic and has a Mohs hardness of about 6.5 to 7.0 depending on the composition.

The Latin version of the name, lapis nephriticus, is the origin of the term nephrite, another variety of jade. Jadeite is formed in metamorphic rocks under high pressure and relatively low temperature. In all well-documented occurrences, jadeitite appears to have formed from subduction zone fluids in association with serpentinite.

Jadeite from the Motagua Valley, Guatemala, was used by the Olmec and Maya, as well as the indigenous peoples of Costa Rica.

Typically, the most highly valued colors of jadeite are the most intensely green, translucent varieties, though traditionally white has been considered the most valuable of the jades by the Chinese.

Natural Icy Imperial Emerald Green Jadeite Dragon's Fang Pendant 16 carats.
Top-quality jadeite is very rare. Vivid, sleek, and translucent, magnificent jadeite commands some of the highest prices among gems in today’s international market. Jadeite’s three most important qualities, in order of their impact on its market value, are color, transparency, and texture.

The finest-quality jadeite is known as Imperial jade. The royal court of China once had a standing order for all available material of this kind, and it’s one of the world’s most expensive gems.

The Hutton-Mdivani necklace by Cartier sold for $27.4 million, a world record for a Cartier jewel.

Jadeite and diamond pendant £180k
Jadeite’s transparency ranges from opaque to semitransparent. The best jadeite is semitransparent. The finest-quality jadeite is usually cut into cabochons.

A jadeite snuff bottle, 1780–1880. It sold for HK$ 1.5 million

A pair of jadeite and diamond ear pendants. Est HK$3,800,000-5,800,000 ($480,000-750,000)

A magnificent jadeite ring. Est HK$28,000,000-38,000,000 ($3,500,000-4,800,000)

Art-deco jadeite, enamel, gem-set and diamond brooch from Cartier, circa 1927. HK$7,000,000-8,000,000

Jadite Bangle. HK$6,000,000 – HK$8,000,000 ($777,816 - $1,037,088)


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Kunzite
Kunzite is the best-known variety of the mineral spodumene. It’s named after gemologist George Frederick Kunz, who was the first to identify it as a unique variety of spodumene around 1902. Kunzite gets its color from trace amounts of manganese. California’s San Diego County is an important source of kunzite. It’s also found in Afghanistan, Brazil, and Madagascar.
It is not unusual to find kunzite in large sizes. The Smithsonian Institution houses a faceted heart-shaped kunzite that weighs 880 carats. Kunzite can be irradiated and then heat-treated to enhance its color. Both treated and natural color in kunzite can fade with exposure to heat and bright light.

Kunzite rates 6.5 to 7.0 on the mohs hardness scale, making it ideal for jewellry.
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Kyanite
Kyanite is composed of aluminum silicate; the same as andalusite and sillimanite. Kyanite has a different crystal structure (triclinic) and thus exhibits different physical properties. One of the unusual properties of kyanite is that it has a variable hardness - it is soft when cut parallel to the long axis of the crystal, with a hardness of only 4 to 4.5 on the Mohs scale. But it has a hardness of about 6.5 when cut perpendicular to the long axis. Kyanite has a vitreous to pearly luster. Generally kyanite gems are not found in large sizes
Blue kyanite has long been used as a sapphire imitation. Bright blue kyanite from Nepal might be mistaken for sapphire, but they are easily identified by their different inclusions and optical values. Recent finds of very high quality kyanite in Nepal are changing perceptions of this gem.

Daha is in Jajarkot District in the Bheri Zone of Mid-Western Nepal. Four small-scale kyanite mines are currently in operation in Daha and Suneri in Jajarkot, and Barah in Aachham District. Production is very limited. High quality inky blue kyanite crystals are cut for gems.
Until recently, it was believed that kyanite always formed in shades of blue.

But orange kyanite has now been discovered in Tanzania. The orange color is derived from trace amounts of manganese in the crystals. Kyanite’s name does reflect the more common blue color, and is derived from the Greek word kuanos, which translates to “deep blue.”
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Mandarin Spessartite Garnet
Mandarin Spessartite Garnet is a rare form of orange garnet colored by manganese.

The combination of vivid color and garnet's very high refractive index make spessartite garnet one of the most brilliant stones in the world of colored gems. Its hardness is around 6.5 - 7.5 on the Mohs scale, making it ideal for jewelry.
The gems occur in a range of colors from yellowish orange to reddish orange and orange-red. The pure orange, known as mandarin or fanta orange, is very rare and has been found in only a few deposits in Africa, notably in Nigeria.

Top spessartites are highly sought after by gem collectors and are considered investment grade. Very little in the way of new material has been found recently.
The prices and value of spessartite garnet varies according to the size and quality of the gemstone. Color and clarity are the most important factors. Vivid orange is the most valuable. The reddish and orange-red are also valuable in fine quality. Gems with a distinct brownish hue, or heavily included stones, are less valuable.

Spessartites are not currently enhanced by any method.
Harry Winston
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Padparadscha Sapphires
The most prized of all the sapphires and highly regarded throughout the ages, padparadscha sapphires are as beautiful and exotic as their name.

The term padparadscha is derived from the Singhalese word for a salmon colored lotus blossom. Overall, padparadscha sapphires are pinkish orange in color, but vary in hue and tone.
The question of just what exactly qualifies for the princely kiss of “padparadscha” is a matter of debate, even among experts.

Today, padparadscha is narrowly defined by gemologists as a Sri Lankan sapphire of delicate pinkish orange color.
Most lotus blossoms are far more pink than orange, and in ancient times, padmaraga was described as a subvariety of ruby. Today, some define the gem's color as a blend of lotus and sunset.
The original source for padparadscha is Sri Lanka (Ceylon) and purists today believe the term should be restricted only to stones from Ceylon. However, fine stones have also been found in Vietnam’s Quy Chau district, Tanzania’s Tunduru district, and Madagascar.

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Paraiba Tourmaline
Tourmaline is a crystal boron silicate mineral compounded with elements such as aluminium, iron, magnesium, sodium, lithium, or potassium.

Tourmaline is classified as a semi-precious stone and comes in a wide variety of colours. Almost every colour of tourmaline can be found in Brazil, especially in the Brazilian states of Minas Gerais and Bahia. In 1989, miners discovered a unique and brightly colored variety of tourmaline in the state of Paraíba.
The new type of tourmaline, known as paraiba tourmaline, came in blue and green. Brazilian paraiba tourmaline usually contains abundant inclusions. It was found the element copper was important in the coloration of the stone. These cupriferous tourmalines are small, rare and precious.

Their turquoise to green colours are not duplicated in any other gemstone in the world.
Another highly valuable variety is chrome tourmaline, a rare type of dravite tourmaline from Tanzania. Chrome tourmaline is a rich green colour due to the presence of chromium atoms in the crystal; chromium also produces the green colour of emeralds.
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Red Beryl
Red beryl is an extremely rare variety of beryl that receives its red color from trace amounts of manganese. World-wide, crystals suitable for cutting gems have been found in one location only, the Ruby-Violet claims in the Wah Wah Mountains of Beaver County, Utah. The Utah Geological Survey estimated that one crystal of red beryl is found for every 150,000 gem-quality diamonds.

Red beryl is extremely rare because its formation requires a unique geochemical environment. First, the element beryllium must be present in large enough amounts to form minerals. Second, dissolved manganese must also be present at the same time and location. Third, the correct geochemical conditions must be present for beryllium, manganese, aluminum, silicon, and oxygen to crystallize into red beryl. Fractures and cavities must also be available to serve as a space for the crystals to grow.

At the Ruby-Violet mine, the topaz rhyolite is a lava flow that erupted from volcanic vents about 18 to 20 million years ago. As the lava flow cooled, fractures and cavities developed in the rock. These openings allowed superheated beryllium-rich water and gases to enter the formation. These were released from a magma chamber that was degassing below.

At the same time, surface water was entering fractures above and moving downwards. It carried oxygen, manganese, aluminum, and silicon leached from the rocks above.
Superheated water and gases from below encountered cool waters from above, which produced a change in geochemical conditions that triggered mineral crystallization.

Red beryl rough is rarely larger than one carat and most faceted red beryls are 0.2 carat or less. Most specimens of red beryl from Ruby-Violet have a rich saturated red color. This allows tiny faceted stones to exhibit a vivid red color.
Lab-created red beryl was first produced in Russia by the hydrothermal process in the mid-1990s. As of January 2016, the lab was no longer producing red beryl. Lab-created red beryl has the same composition and physical properties as natural red beryl but gemologists familiar with the materials are able to distinguish lab-created from natural.

The name "red emerald" is sometimes used when referring to red beryl. This name is a misnomer because emerald, by definition, is green.
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Rubellite/Pink Tourmaline
There has been increased interest in fine pink tourmaline gems. A major reason is the market for pink tourmaline, like much of the jewelry industry, is driven by Chinese demand, where growing wealth has fueled an insatiable appetite for fine jewelry.

Elbaite is the most well-known and valuable form of tourmaline. Almost all of the tourmaline gemstones are of the elbaite variety.

Wallace Chan's ’Vividity’ brooch, with a rare elbaite tourmaline in the centre.

Empress Dowager Tz’u Hsi. A large pink tourmaline, along with pearls, adorns her headdress.
China’s demand for pink tourmaline, and the pinkish-red variety known as rubellite, is not new. Part of this penchant for the pink stone is owed to the fact that pink tourmaline was the favorite gemstone of the Empress Dowager Tz’u Hsi of China in the late 19th century.

During the late 1800s, much of the pink and red tourmaline mined in California, where the gem was first found in 1890s, was shipped to China.
The gemstone’s popularity has pushed prices for high quality pieces to ever higher levels.
Today most tourmaline comes from Africa, particularly Mozambique, Namibia, Nigeria and Tanzania.

Tourmaline is a silicate compounded with aluminum, iron, magnesium, sodium, lithium or potassium. Tourmaline has a hardness level of 7 to 7.5 on the Mohs scale. It is extremely durable. The best tourmaline displays excellent transparency and a vitreous luster.

White gold, one 14.27-carat cushion-shaped rubellite, brilliants. Cartier.

Platinum, mandarin garnets, pink tourmalines, tanzanites, tsavorite garnets, yellow diamonds, brilliants. Cartier.

Hemmerle often incorporates large, vivid colored pink tourmalines and rubellites.

Robert Procop ring featuring a 31.74-carat rubellite surrounded by a melange of pavé diamonds, pink sapphires and rubies.

Buccellati Dream Cuff Bracelet in white and yellow gold with tourmaline and diamonds

Panthère de Cartier Bracelet set with a rubellite, pink sapphires, diamonds and onyx

Van Cleef & Arpels Lady’s Cocktail Ring set with diamonds, carved rubellite and turquoise
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Star Ruby - Star Sapphire
Star rubies and star sapphires display a six-ray star that seems to glide across the surface of the gem when moved. This six-ray star is caused due to an optical phenomena known as "asterism".

The term is derived from the Greek word "aster", which means star, so asterism is commonly referred to as "star" or "star-effect". Other popular gemstones that display asterism are rose quartz, garnet, diopside, moonstone, spinel and opal.
Black Star Sapphires with golden stars are one of the most fascinating forms of sapphire. Black star sapphires differ from other colours of star sapphires because the star is formed not due to rutile silk but due to hematite plates.
The Delong Star Ruby resides in the Natural History Museum in New York City. Weighing 100.32 carats, it is a purplish red stone from Burma.

The Rosser Reeves Star Ruby; a fine-quality star ruby of 138.70 carats from Sri Lanka.
Star of Asia A round six-ray star sapphire weighing 329.7 carats. The stone's origin is Burma, and it's part of the Smithsonian Museum's collection.

Weighing 27.62 carats, the Star of Bharany Ruby is one of the world’s finest star rubies.
Traditionally, star rubies were worn by knights in the battlefields to protect themselves from the enemy. Local tales in Karnataka (India) say that if it is worn as a visible pendant or as a headgear then anyone who faces you as an enemy looses half his valour.

The power of star ruby is said to be the highest during full moon.
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Tanzanite
Tanzanite is the blue/purple variety of the mineral zoisite. It was discovered in the Mererani Hills of Manyara Region in Northern Tanzania in 1967, near the city of Arusha and Mount Kilimanjaro.

Naturally formed tanzanite is extremely rare. Tanzanite is noted for its remarkably strong trichroism, appearing alternately sapphire blue, violet and burgundy depending on crystal orientation.
Tanzanite is a relatively new gemstone in the world of gemology and jewelry. Since its discovery, tanzanite has sold for as little as $20 per carat and as much as $1,000 per carat or more, for gem-quality, finely coloured stones.
That price may seem like a bargain in time, as tanzanite is a one-source gemstone and that source is expected to be mined out within the next 15 to 25 years.
Pleochroic means tanzanite offers three distinct colors in three crystal directions. Tanzanite has a Mohs hardness of 6 to 7.
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Tsavorite Garnet
Tsavorite is a variety of the garnet group, a calcium-aluminium garnet with the formula Ca3Al2Si3O12. Trace amounts of vanadium or chromium provide the green color. Green colors of tsavorite and demantoid overlap, but they are different garnet group minerals. Tsavorite is green grossular and demantoid is green andradite. Andradite is softer than grossular with a higher refractive index and higher dispersion.

The name tsavorite was created by Tiffany in honor of Tsavo East National Park in Kenya. Apart from Tanzania it is also found in Madagascar. Small deposits of gem grade material have been found in Pakistan and Queen Maud Land, Antarctica. No other occurrences of gem material have been discovered.
Tsavorite Garnet is a rare gem that has begun to challenge emerald as the finest of the green gemstones. Unlike emerald, tsavorite is always untreated. It has more brilliance than emerald due to its higher refractive index.

Tsavorite garnets over 2 carats are very rare, and fine stones over 4 carats are exceptionally rare. Colors range from mint green to a deep chrome green.
Tsavorite garnets are famed for their brilliance. Their eye-catching radiance and favourable properties for setting in jewellery makes them highly desirable gems.
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