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Did you know that? Part II

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hahahahhaaaa!!! at 58 and me blushing, no way.. there is nothing to blush but natural surroundings in cold weather can paint anyone's cheeks to blush
 
#18. Bixbite



Emeralds including Golden Beryl and aquamarine is the most famous in the family of beryl. But emerald is by no means the rarest of the beryls. That distinction belongs to bixbite – the red beryl. All the members of the beryl family are beryllium aluminum cyclosilicate by chemical composition.

Pure beryl is actually colorless. The various colors occur from the presence of impurities. Presence of chromium and vanadium forms Emerald. Presence of iron forms aquamarine and gold beryl. Presence of manganese forms morganite and bixbite. Goshenite is white or colorless beryl.

Bixbite was first discovered in 1904 in the Thomas Mountains in western Utah, USA. It was named after Maynard Bixby (1853-1935), an American mineralogist.

Concentration of red beryl was very small and the material did not possess gem quality. Gem-quality material was found in 1958 in the Wah Wah mountains of Beaver County, in southwestern Utah.

Prices for the top quality natural red beryl can be as high as $10,000 per carat for faceted stones. Most red beryl specimens weigh less than a carat. Red beryl is very rare and is found only in very few locations like Wah Wah mountains-Utah, Paramount Canyon, and Round mountain.

Red beryl has been known to be confused with pezzottaite also known as raspberry beryl or “rasp beryl”, a red gemstone that has been found in Madagascar and now Afghanistan. But the cut gems of the two varieties can be easily distinguished since they have different refractive indices.
 
#19. Black Opal




Opal is the ‘Queen of Gems’. It is unique among gemstones since no two Opals are ever exactly alike! The colors and patterns within each stone also changes with the angle of view. These flashes of colors make opal a truly fascinating gem. Opal has long been associated with good luck.

The term Black Opal is misleading as the opal is not ‘black’ in color. It has a very dark base body color, which enhances the brilliance of the diffracted colors. Opal is an amorphous form of silica related to quartz.

It is a mineraloid and not a mineral since water forms 3% to 21% by weight. Opal is the national gemstone of Australia, which produces 97% of the world’s supply. South Australia alone meets 80%of the world’s demands.

Opal diffracts light due to its internal structure. It can take on many colors depending on the conditions in which it formed. Opal ranges from clear through white, gray, red, orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, and black.

Of these hues, the reds against black are the rarest, whereas white and greens are the most common. Its optical density varies from opaque to semi-transparent.

While used as a gemstone, thin layers of opal are placed on basalt – a darker underlying stone, enhancing the natural colors of the opal.
 
#20. Bloodstone




Bloodstone was the original birthstone for March. Now aquamarine, jasper and bloodstone, are all considered as birthstones for March. Bloodstone is a silicon dioxide and a variety of chalcedony.


It is a dark green colored jasper with red spots caused by the presence of iron oxide. These red spots have given the gem its name. The deep green color is due to the presence of chlorite. Jasper with yellow or other colors are usually called “fancy jasper”.


A good quality bloodstone is solid green in color with blood-red spots. The gemstone is cut into round, oval, cushion cut, octagonal, cabochon and emerald cut.


Bloodstone set in jewelry is coated with a special polish. Exposure to strong detergents or harsh chemicals would damage the special polish given to the surface.


When bloodstone is rubbed on a porcelain surface, it leaves blood-red scars. Today India is the major source of bloodstone. There are also deposits in Brazil, China, Australia and United states.


Bloodstone is attributed with many healing Properties like improving blood circulation, curing blood poisoning, and stopping bleeding. It protects from evil eyes and warns the wearer of imminent dangers by turning blood red in color. It brings good luck, gives a long life span and keeps the person in good mood.
 
#21. Boulder Opal



Opal is an amorphous form of silica related to quartz. It is a mineraloid and not a mineral since water forms 3% to 21% by weight.

Opal is the national gemstone of Australia, which produces 97% of the world’s supply. South Australia alone meets 80% of the world’s demands.

Opal diffracts light due to its internal structure. It can take on many colors depending on the conditions in which it formed. Opal ranges from clear through white, gray, red, orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, and black.

Of these hues, the reds against black are the most rare, whereas white and greens are the most common. Its optical density varies from opaque to semi-transparent.

While used as a gemstone, thin layers of opal are placed on basalt – a darker underlying stone, enhancing the natural colors of the opal.

Boulder Opals are the second most valuable opals after the black opals. Boulder Opal is unique to Queensland Australia.

It occurs in deposits in weathered sedimentary Cretaceous rocks in the west of the state. It is found in siliceous ironstone concretions or boulders ranging in size from less than a few centimeters to more than 20 cm.

Major boulder opal mines are at Winton, Quilpie, Yowah, Koroit and Jundah. Concretions up to 5 cm across are known as ‘nuts’. These may host a kernel of solid opal or contain a network of thin veins of opal through the ironstone.

The opal veins are tricky to follow. Many cutters split the boulder with a saw to expose spectacular colors of the rainbow. Sometimes it looks like both pieces have been polished. Such splits are used in making earrings since it is very hard to get 2 pieces of opal matching in color.

Ironstone from Koroit has very little color but have interesting patterns in black and white. Some of the brightest colors are found in Yowah nuts.

Quilpie and Winton have some beautiful opals that have full face of color. These thin color bars need good cutters with experience.
 
#22. Calcite




Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate CaCO3. Aragonite and vaterite the other two forms which are very unstable.

Calcite measures 3 on Mohs scale of hardness. Its luster is vitreous in crystallized varieties. Color may be white or none, though shades of gray, red, orange, yellow, green, blue, violet, brown, or even black can occur when the mineral is charged with certain impurities.

Calcite is transparent to opaque and may occasionally exhibit Phosphorescence and fluorescence. Iceland spar, a transparent variety is used for optical purposes.

The largest documented single crystals of calcite originated from Iceland, measured 7×7×2 m and 6×6×3 m and weighed about 250 tons.

Calcite is found in spectacular form in the Snowy River cave of New Mexico, where micro-organisms are credited with natural formations.
 
#23. Carnelian



Carnelian is a brownish-red mineral commonly used as a semi-precious gemstone. Sard is similar to carnelian but is generally harder and darker. The difference is not rigidly defined and hence the two names are often interchanged.

Both carnelian and sard are varieties of the silica mineral chalcedony colored by iron oxide as an impurity. The color can vary greatly, ranging from pale orange to an intense almost-black coloration.

Carnelian is one of the birthstones listed in the ancient Arabic, Hebrew, Italian and Roman tables and is a Zodiac birthstone for the signs of Leo and Virgo. Most Carnelian is heat treated today to enhance its natural color.

Folklore suggests that carnelian was used protect the traveler after death. Carnelian helps to purify the blood. It relieves menstrual cramps and back pain. It is worn to enhance passion and desire in women.

Carnelian is a 7 on the Moh’s hardness. It has been used to carve beautiful cameos since many centuries. It is found in Australia, Brazil, Madagascar, Russia, South Africa, and the USA.
 
#24. Cassiterite



Cassiterite is SnO2 or Tin oxide mineral. It is generally opaque but it is translucent in thin crystals. Its luster and multiple crystal faces produce a desirable gem. Cassiterite has been the chief ore of tin throughout in the past and remains the most important source of tin today.

Cassiterite is the most important ore of tin and is marked with high durability. The name of this mineral is derived from the word “Cassiterides” which was the word used to describe British islands in pre-Roman times.

Their most prevalent usage is as gemstones. The name Cassiterite was derived from a Greek word “kassiteros” which stands for tin. It is also popularly known as ‘tinstones’.

Cassiterite occurs in pegmatites and can be washed into alluvial deposits. Localities include the Malay Peninsula, England, Germany, Australia, Bolivia, Mexico and Namibia.

Cassiterite is a rare natural gemstone. Its color can be black, brownish black, brown, gray, yellowish, greenish, red or even colorless. It has a hardness of 6 to 7 on the Moh’s scales. Cassiterite has much more dispersive fire than even diamond. It is one of the rarest gemstones.

Cassiterite is primarily concentrated in alluvial surfaces. They are mainly available in the tin mines located in Bolivia where they exist in hydrothermal veins. This type of ore is available in small elements that are derived from igneous rocks.

The different aspects of this ore are elaborately arranged and exhibit tremendous amount of luster. Associated minerals with which cassiterite ores are generally found are Tourmalines, Molybdenite, Bismuthinite, Topaz, Fluorite, and Wolframite.
 
#25. Cat’s Eye Apatite



Cat’s Eye Apatite colors

The range of colors includes pink, yellow, green, blue and violet in addition to the colorless.

A rare variety is the rich purple from Maine. The second in demand is Blue Brazilian stone.The “asparagus stone” is a light green variety of apatite.

The use of apatite in jewelry has been boosted by the neon blue-green variety from Madagascar. It is the color saturation that decides the value of the gem.

The cat’s eye effect, ‘Chatoyancy’ is the reflection of light by parallel fibers, needles, or channels, which resembles the slit eye of a cat.

When the stone is rotated, the gleam of light glides over the surface.
This is usually a transparent gemstone. The cabochon cut is excellent for a unique brooch or pendant, if its base is parallel to the fibers.

Cat’s eye apatite is very rare. Apatite are found in Brazil, India, Kenya, Madagascar, Mexico, Myanmar (Burma), Norway, Sri Lanka, South Africa and the United States.
 
#26. Cat’s Eye Aquamarine




Chatoyancy or chatoyance, is an optical effect seen in some opaque or translucent gemstones. Chatoyancy is caused by the fibrous structure of a material, or by the fibrous inclusions or cavities within the stone.

Precipitates of rutile titanium oxide cause chatoyance. The rutile precipitates are all aligned perpendicularly with respect to cat’s eye effect.

The effect is similar to the sheen off a spool of silk. The luminous streak of reflected light is perpendicular to the fibers. A gemstone cut with the fibers parallel to the base exhibit chatoyancy. Faceted stones are less likely to show the effect well.

The term Cat’s Eye can only refer to a Cat’s Eye Chrysoberyl. Any other stone needs to be identified like Cat’s Eye Aquamarine.

Aquamarine Cats-eyes are fairly rare. It is a collector’s gem. The highly lustrous Aquamarine Cats-eye comes in a variety of Blue shades from sky blue to deep Sea – blue.

A rare form of aquamarine is translucent with a cat’s eye effect, known as a cabochon. This effect resembles the slit of a cat’s eye and appears to move over the surface.
 
#27. Cat’s eye Scapolite




Scapolite is a sodium calcium aluminum silicate with a complex chemical composition. The name Scapolite represents a series of minerals between Marialite (rich in sodium chloride) and Meionite (rich in calcium carbonate).

Distinguishing the scapolite minerals from one another is difficult. They differ only slightly in density and refractive index. With the increase of the calcium content, both density and the refractive index increase.

Scapolite gemstone is transparent. The less transparent material cut as cabachons exhibit the cat’s eye effect. Chatoyancy or chatoyance, is an optical effect seen in some opaque or translucent gemstones.

Chatoyancy is caused by the fibrous structure of a material, or by the fibrous inclusions or cavities within the stone. Precipitates of rutile titanium oxide cause chatoyancy. The rutile precipitates are all aligned perpendicularly with respect to cat’s eye effect.

The effect is similar to the sheen off a spool of silk. The luminous streak of reflected light is perpendicular to the fibers. A gemstone cut with the fibers parallel to the base exhibit chatoyancy. Faceted stones are less likely to show the effect well.

Scapolite Cat’s eye stones are rare and valuable since they have exceptionally sharp eyes. Scapolite is found in Canada, the USA, Norway, Italy and Mexico. Gemstone sources are found in Brazil, Madagascar, Tanzania, Kenya, Canada and Burma.
 
#28. Cat’s eye Tourmaline





The Sri Lankan expression “tura malli” means ‘a stone of many colors’. Tourmaline is available in a range of colors and some stones even show bi-coloration. It has been called the “rainbow gemstone”.

Ancient Egyptian belief was that when Tourmaline traveled from the depths of the earth to its surface, it brought a rainbow in order to announce its arrival.

Due to Tourmaline’s electrical properties it has often been used to transfer energy and for cleaning the pipes. The Dutch brought Tourmaline to Europe in 1703. It was then used to clean pipes utilizing its piezoelectric property to attract small particles of dust and ash.

Chatoyancy or chatoyance, is an optical effect seen in some opaque or translucent gemstones. Chatoyancy is caused by the fibrous structure of a material, or by the fibrous inclusions or cavities within the stone. The rutile precipitates are all aligned perpendicularly with respect to cat’s eye effect.

The effect is similar to the sheen off a spool of silk. The luminous streak of reflected light is perpendicular to the fibers. A gemstone cut with the fibers parallel to the base exhibit chatoyancy. Faceted stones are less likely to show the effect well.

Tourmaline is believed to be a spiritual stone which can stimulate the artistic assets of its wearer. Cat’s eye Tourmaline is considered rather rare, distinguished by its beauty and coloration.

Tourmaline is is a cyclosilicate mineral found in pegmatites, granite and marble. It is found with elements such as aluminum, iron, magnesium and potassium.

Minas Gerais mines in Brazil yield the world’s most beautiful Tourmaline gemstones. Tourmaline comes in many species and varieties, named after the specific localities in which they were found.

Tourmaline must be cleaned only with soap and water. Colorful tourmaline gems are extremely fragile and should be stored away from harder stones.
 
#29. Chalcedony



Chalcedony is a polycrystalline form of silica, composed of very fine inter growths of quartz and moganite. Chalcedony’s standard chemical structure is SiO2 (Silicon Dioxide).

Chalcedony has a waxy luster. It may be semitransparent or translucent. It can assume a wide range of colors, but the most commonly seen are white to gray, grayish-blue and a shade of brown ranging from pale brown to nearly black.

In the Bronze age, chalcedony was in use in the Mediterranean region. Some chalcedony seals recovered date back to 1800 B.C. People living along the Central Asian trade routes used various forms of chalcedony, to carve intaglios, ring bezels with the upper faceted portion of a gem projecting from the ring setting and beads that show strong Greece-Roman influence.

Hot wax would not stick to it so it was often used to make seal
impressions.

Originally the agate carving industry around Idar and Oberstein was driven by local deposits that were mined in the 15th century. In the 19th century Idar-Oberstein became the world’s largest chalcedony processing center, in particular agates. Most of these agates were sourced in Latin America, in particular Brazil.

Several factors contributed to the re-emergence of Idar-Oberstein as agate center of the world. Ships brought agate nodules back as ballast providing cheap transport. Cheap labor and a superior knowledge of chemistry which allowed them to dye the agates in any color using well guarded secret methods helped.

Each mill in Idar-Oberstein had four or five grindstones. These were of red sandstone and two men usually worked together at the same stone.
 
#30. Charoite



Charoite is a rare silicate mineral. It was first described in 1978 and named after the Chara River. It has been reported only from the Sakha Republic, Yakutia, Siberia, Russia.

Charoite is translucent with a pearly luster and varies from lavender to purple in color. Charoite is strictly massive in nature, and all fractures are conchoidal.

It has an unusual swirling, fibrous appearance, sometimes exhibits chatoyancy. This fact along with its intense color may lead many people to mistake that it is either produced synthetically or enhanced artificially.

Though discovered in the 1940s according to reports, it was known to the outside world only after its description in 1978. It is said to be opaque and unattractive when found in the field; a fact that may have contributed to its late recognition. But after it is prepared it becomes an eye catching beauty.
 
#31. Chocolate Opal


This opal from Ethiopia is Volcanic origin. It is formed in a nodule. Only a very small percentage of the collected opal has a good fire and an attractive play of colors. This opal is loved by many polishers, carvers and specimen collectors world wide for its amazing fire play.

This material has been nicknamed “chocolate opal” due to the dark brown base. Because of the dark body color, Red, green, blue and orange fire seem to well up within the stone, rather than flash out.

Ethiopia Chocolate and Crystal Shewa Province Nodule Opals are found at Yita Ridge, in the Menz Gishe District of Shewa Province. It is situated about 150 miles northeast of the capital of Ethiopia – Addis Ababa . The opal field extends for several square kilometers along the northern side of the Yita Ridge.

The opals are found in a nodular form within a continuous layer of welded volcanic ash. These nodules are quite numerous but the percentage of gem quality opal is quite small. About one sixth of the opal recovered has the gem quality and one in a hundred shows distinct play of color.

It should be noted that most of the nodules show internal fractures in this type of opal. But some nodules are cut so as to show no fractures at all. These cabochons are very precious. The most coveted of these nodules have center opal showing brilliant neon colors across the entire spectrum.
 
#32. Chrome diopside



Diopside is a monoclinic pyroxene mineral with composition MgCaSi2O6. It forms dull green crystals in various shades. It has two distinct prismatic cleavages at 87 and 93° typical of the pyroxene series. It measures 6 on Moh’s scale of hardness and is transparent to translucent.

Diopside of gem quality is found in two forms: the black star diopside and the chrome diopside with a rich green color. Chrome diopside is relatively soft to scratch since is has a hardness of only 5.5 to 6.5 on the Moh’s scale of hardness.

Violane is a diopside rich in manganese and varies from violet to light blue in color.
 
#33. Chrome tourmaline



Tourmaline is a crystal boron silicate mineral compounded with elements such as aluminium, iron, magnesuim, sodium, lithium and potassium.

Tourmaline is semi precious stone and comes in a wide variety of colors. The name is derived from the Sinhalese word “Thuramali” or “Thoramalli” which applied to different gemstones found in Sri Lanka.

Tourmaline varies from transparent to translucent and exists in a variety of colors. Tourmalines rich in iron vary from black or bluish-black to deep brown. Those rich in magnesium vary from brown to yellow. The tourmalines rich in lithium may be of any color: blue, green, red, yellow, pink, etc. Tourmaline is rarely colorless.

Bi-colored and multicolored crystals are common, reflecting variations of fluid chemistry during crystallization. Crystals may be green at one end and pink at the other, or green on the outside and pink inside.

This type of tourmaline is called watermelon tourmaline. Some forms of tourmaline exhibit Dichroism. They change color when viewed from different directions.

The pink color of tourmalines from many fields is the result of a continued natural irradiation. Initially they are by nature very pale. During their growth, these tourmalines acquire pink to red color.
 
#34. Chrysoberyl



The mineral and gemstone chrysoberyl is an aluminate of beryllium. The name is derived from the Greek words chrysos and beryllos, meaning “a gold-white spar”.

Ordinary chrysoberyl is yellowish-green in color and can vary from transparent to translucent. The mineral when it is transparent and exhibits a pale green to yellow color, it is used as a gemstone.

The three main varieties of chrysoberyl are: ordinary yellow-to-green chrysoberyl, cat’s eye or cymophane, and alexandrite. Yellow-green chrysoberyl was referred to as “chrysolite” in the past, but that name is no longer used now.

Chrysoberyl was first discovered in 1789 and described and named in 1790, by Abraham Werner who was one of the most outstanding geologists of his time.

Chrysoberyl and beryl are two completely different gemstones. Chrysoberyl is a hard natural gemstone and lies at 8.5 on the Moh’s scale of harness between corundum (9) and topaz (8).

Members of the beryl group include emerald, aquamarine, and morganite while members of the chrysoberyl group include chrysoberyl, cymophane (cat’s eye), and alexandrite.

Beryl is a silicate and chrysoberyl is an oxide. Though both beryl and chrysoberyl contain beryllium they are two different gemstone species unrelated in any other way.

Because of the confusion between chrysoberyl and beryl, chrysoberyl remains relatively unknown for its won merits while the alexandrite variety is much more widely recognized. The two well-known natural gemstones harder than chrysoberyl are corundum and diamond.





 
#35. Chrysoberyl cat’s eye




Tourmaline, corundum, spinel , scapolite and quartz can exhibit chatoyancy and form “cat’s eye” similar in appearance to cymophane.

The jewelry industry designates these stones specific names as “quartz cat’s eyes”, or “ruby cat’s eyes” and only chrysoberyl can be simply referred to as “cat’s eye” with no other designation.

Gems lacking the silky inclusions required to produce the cat’s eye effect are usually faceted. An alexandrite cat’s eye is a chrysoberyl cat’s eye that changes color.

“Milk and honey” is a term commonly used to describe the color of the best cat’s eyes. The effect refers to the sharp milky ray of white light normally crossing the oval shaped cabochon as a center line along its length and overlying the honey colored background.

The honey color is considered to be top-grade by many gemologists but the lemon yellow colors are also popular and attractive. Cat’s eye forms only a small percentage of the overall production of chrysoberyl.

Cat’s eye became very popular by the end of the 19th century. Until that time, cat’s eye had been present in gem and mineral collections.

The popularity and the value of the stone increased so much that in the early 20th century the prices could go up as high as $8000 for a cut stone.
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#36. Chrysocolla




Chrysocolla is a hydrated copper silicate mineral. The name comes from the Greek “chrysos” meaning “gold”, and “kolla” meaning “glue”. It is an allusion to the name of the material used to solder gold. It was first used in 315 BC.

It is of a secondary origin. It forms in the oxidation zones of copper ore bodies. Quartz, limonite, azurite, malachite, cuprite and other secondary copper minerals are the other associated minerals. Turquoise and chrysocolla are sometime mistaken for each other due to their very similar colors.

Notable places of occurrences include Arizona, Utah, Idaho, New Mexico and Pennsylvania in the U.S.A, Israel, Democratic republic of Congo, Chile and Cornwall in England. A 2006 study has produced evidence that chrysocolla may be a microscopic mixture of the copper hydroxide mineral spertiniite, amorphous silica and water.

Color is a unique green-blue but can vary widely from richer blue to richer green in the same specimen. It has a dull and waxy luster and may be opaque or translucent.

Fractures are conchoidal and the hardness lies between 2 and 4 on Moh’s scale of hardness. Chrysocolla may resemble an opal in appearance.



 
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