Abalone is a single-shelled marine mollusk that has been highly prized for thousands of years, and for multiple reasons. This amazing creature has been, and still is, harvested as a food source. Its mild, sweet meat is considered a delicacy by gourmets around the world. Its shell, which is valued by jewelry manufacturers, exhibits colorful, richly-textured iridescent patterns that border on kaleidoscopic. Its greatest treasure, however, is a pearl. It has been reported that fewer than 1 in 10,000 shells produce a pearl, and that less than 1 out of 100,000 exhibit symmetry. Most are irregular or horn shaped.
Agate is gemologically described as a cryptocrystalline variety of quartz. Rather than a single crystal, it is composed of myriad miniature crystals that can only be seen with extreme magnification. In appearance agate is often banded. The concentric bands may be oval, rounded, elliptical, or totally irregular in shape, and may be multiple colors, or different shades of a single color. Agates can be found throughout the world, but a few notable sources include Brazil, China, India, Madagascar, Mexico, and the USA.
Named in honor of Czar Alexander II of Russia, alexandrite is actually a very special variety of the mineral chrysoberyl. It exhibits an exotic and highly prized optical property known as color change. When held in daylight, it appears greenish, but when held under the warm lights of candles or incandescent bulbs, it appears reddish. Even more exotic is the doubly special cat’s-eye alexandrite. This variety of chrysoberyl exhibits both color change, and a special property known as chatoyancy. The most well-known source of alexandrite was Russia (Urals); however these deposits have played out. Notable sources now include Brazil, India, Sri Lanka, and Tanzania.
(almandine garnet) Almandite is a member of the garnet group of gemstones. It is one of six species recognized by gemologists. The dominant hue is red, but the overall color may be modified by a little violet. Chemically it is an iron-aluminum silicate, but is rarely pure in nature. Almandite is very popular in jewelry since it is hard (7.5) and durable. Important sources include Brazil, India, Madagascar, Sri Lanka, and the USA.
Amazonite (sometimes called "Amazon stone") is a green variety of microcline feldspar. The name is taken from that of the Amazon River, from which certain green stones were formerly obtained, but it is doubtful whether green feldspar occurs in the Amazon area. Amazonite is a mineral of limited occurrence. Formerly it was obtained almost exclusively from the area of Miass in the Ilmen mountains, 50 miles southwest of Chelyabinsk, Russia, where it occurs in granitic rocks. More recently, high-quality crystals have been obtained from Pike's Peak, Colorado, where it is found associated with smoky quartz, orthoclase, and albite in a coarse granite or pegmatite. Crystal Park, El Paso County, Colorado is a well-known locality for crystals of amazonite. Some other localities in the United States yield amazonite, and it is also found in pegmatite in Madagascar and in Brazil. Because of its bright green colour when polished, amazonite is sometimes cut and used as a gemstone, although it is easily fractured.
Amber is the generic name applied to various types of hardened, fossilized resins. It is one of the oldest organic gem materials known to man. Scientists often refer to amber as succinite or retinite. Many variety names are found throughout the world (rumenite, simetite, burmite, etc.). There is no clearly defined consensus on what constitutes amber versus copal (baby amber), since scientists are still debating the relevance of chemistry, age, and other factors. Some of the oldest amber has been dated back to the Carboniferous period – nearly 320 million years ago. This makes even Baltic amber (approximately 30 million years old) young by comparison. Amber is extremely popular in jewelry, but is also prized by collectors for the variety of plants, animals and insects that are often found within. Sources of amber are varied, but include China, Canada, the Dominican Republic, Italy, Myanmar, Rumania, the USA and many countries bordering the Baltic Sea.
Amethyst is one of the better-known members of the quartz family. Color can range from soft lilac to intense purple or violet. Most amethyst is made by heating citrine, another member of the quartz family. Amethyst is popular in jewelry and serves as the birthstone for February. Important sources include Brazil, Madagascar, Mexico, Myanmar, Uruguay, the USA, and Zambia.
Ametrine is a bi-color variety of quartz. It is a combination of amethyst and citrine within a single crystal. The primary source of this gemstone is the Anahí mine in Bolivia.
Andalusite is a highly prized collector’s gemstone. It exhibits an optical property known as pleochroism. As the stone is turned or rotated, it exhibits different colors, or blends of colors depending on the angle of viewing. This property is so strong that the color contrast is incredibly striking: earthy, olive greens to rich, reddish browns. Cutters frequently orient stones to maximize the blend of colors. Andalusite was discovered in southern Spain (Andalucía), and derives its name from that locality. Other notable sources include Brazil, Canada, Russia, Sri Lanka, and the United States.
Andradite is one of six gemstone species within the garnet group. It includes several gem varieties, the most notable of which is demantoid, a rare and highly prized green garnet. Rainbow andradite, a rare and exotic variety only found in Japan and Mexico, exhibits an iridescent play-of-color that is visually striking.
Although softer than other species of garnet, andradite is sufficiently durable for use in jewelry. This gemstone was named in honor of J. B. de Andrada e Silva, a distinguished Brazilian scholar.
Apatite is the gemological name applied to a series of related minerals. It can be found in a wide range of colors, but is better known for its blue to green varieties. Softer than many gemstones, apatite is best suited for earrings and pendants, but with proper care can be used in rings and bracelets. An exotic phenomenal variety, known as cat’s-eye apatite, is a highly prized by gemstone collectors. Notable sources include Brazil, India, Madagascar, Mexico, Sri Lanka, and the United States.
Aquamarine is a blue variety of the mineral beryl. Its name is derived from two Latin roots meaning water of the sea. Often referred to as aqua, this gemstone has been prized for many centuries. Cat’s-eye and star varieties are highly prized by collectors. Most aquamarines today have undergone heat treatment to improve color. Irradiation can create deeper blues, but the color can fade quickly when exposed to sunlight.
Notable sources include Brazil, China, India, Madagascar, Myanmar, Nigeria, Sri Lanka, and the United States.
"Black onyx" is neither truly onyx nor truly black, but it is actually dyed chalcedony. According to some experts, it is produced by boiling slabs of gray chalcedony in a sugar solution. The sugar permeates the stone's "pores" between the submicrocrystallites and darkens the appearance of the stone. This dye/treatment is stable and requires no special care.
From the chalcedony family, bloodstone is a medium slightly yellowish-green stone speckled with orangy red spots.
Boulder opal is a precious opal cut to retain some of the surrounding opal matrix, resulting in a unique opal look. It has a dark base surface and can display exciting play of color. On Mohs' scale of hardness, boulder opal is 1.98-2.50. Primary sources include Australia, Brazil, Guatemala, Honduras, Indonesia, Japan, Mexico, Russia, and the United States (Nevada, Idaho).
Carnelian is a variety of cryptocrystalline quartz. It is not a single crystal like amethyst or citrine. Instead, carnelian is an aggregate of myriad microscopic crystals oriented in many different directions. Color ranges from orange to brownish red, and transparency ranges from translucent to opaque.
The term cat’s eye is used to describe an exotic optical property that is rarely seen in many gemstones. The effect, when present, appears as a bright, narrow slit – similar to what you see in the eyes of your favorite feline pet. This phenomenon is caused by parallel fibrous or needle-like inclusions. The inclusions interfere with the passage of light, which is scattered and reflected back to the viewer. The effect is best seen on gems cut en cabochon (a dome-shaped style lacking facets). When used by itself, the term cat’s eye always refers to the chatoyant variety of the mineral chrysoberyl. Any other gemstone exhibiting this optical property must have its name specified: quartz cat’s eye, or cat’s-eye quartz, for example.
Chalcedony is a word that does double duty in the realm of gemology. It is sometimes used to describe a grayish to bluish variety of cryptocrystalline quartz, or may be used as a more generic term to describe all varieties of cryptocrystalline quartzes. In the latter case it is used as a species name. Cryptocrystalline quartz is not a single crystal like amethyst or citrine. It is actually an aggregate composed of numerous microscopic crystals oriented in myriad directions. Other gemstones within the chalcedony species include: carnelian, chrysoprase, sard, and agate.
Chatoyancy is a special optical property that is highly prized by gem collectors. The phenomenon is caused by fibrous or needle-like inclusions that interfere with the passage of light. As the light is scattered, a portion is reflected back to the viewer. If the inclusions are tightly packed, uniform, and parallel, a sharp, narrow line will form. This is called as a cat’s eye. If not uniform, the effect may appear as a less distinct whitish band that moves over the surface of the host. Chatoyancy is best seen in gems cut en cabochon.
Chrysoberyl is a durable, but relatively obscure and unknown gemstone. However, it does have one very famous and highly-prized relative – alexandrite (a color-change variety). Chrysoberyl can be found in colors ranging from golden yellow to green, as well as brownish to reddish brown. Chrysoberyl may exhibit a cat’s eye, which is prized by gem collectors. Alexandrite, the color-change variety of the mineral, may also show the same optical effect. Cat’s-eye alexandrite is very rare. Sources of chrysoberyl include Brazil, Madagascar, Myanmar, Sri Lanka, Russia, and the United States. The cat’s-eye variety can be found in Brazil, China, India, and Sri Lanka. Brazil is the most important source of alexandrite, but rough also comes from Madagascar, Myanmar, Tanzania, and Zimbabwe. The famous deposits of Russia have played out.
Chrysoprase is a beautiful apple-green variety of chalcedony (cryptocrystalline quartz). It can range from translucent to opaque. It has been used as a jade simulant in jewelry. Sources of chrysoprase include Australia (a major producer), Brazil, India, Madagascar, South Africa, Tanzania and the United States (California).
Citrine is one of the better-known members of the quartz family. Naturally occurring citrine is generally a lighter shade of yellow, but heat treated gemstones may range from dark yellow to nearly reddish brown. Most citrine in today’s market is treated. Sources of citrine include Brazil, Madagascar, Namibia, Russia, and the United States.
Coral reefs are underwater structures made from calcium carbonate secreted by corals. Corals are colonies of tiny living animals found in marine waters containing few nutrients. Most coral reefs are built from stony corals, and are formed by polyps that live together in groups. The polyps secrete a hard carbonate exoskeleton which provides support and protection for the body of each polyp. Reefs grow best in warm, shallow, clear, sunny and agitated waters
The mineral name corundum is not well-known to many, but its two gem varieties, ruby and sapphire are. In its purest form, corundum is colorless. It is a combination of aluminum and oxygen (Al2O3) and belongs to the trigonal crystal system. Non-gem varieties of corundum are primarily used as abrasives.
Cubic zirconium (singular) is a man-made gemstone that is commonly used as a diamond simulant. It is a true synthetic since a cubic form of zirconium oxide exists in nature. However, the natural counterpart, which was discovered in the late 1930’s, was of little gemological importance. Cubic zirconia, or CZ, can be found in every color of the rainbow through the use of dopants. Dopants are chemical elements that are added to the synthesis to alter the selective absorption of light. Pink CZ was the first color developed, and was originally marketed as pink ice. CZ is a very durable and affordable alternative to diamond. It is produced by the skull method of synthesis.
An attractively speckled stone, Dalmatine, or “Dalmatian Rock,” consists of extraordinarily curious brown and black minerals embedded in a cream-colored matrix.
Demantoid is a green variety of andradite garnet. It is one of the more-valuable members of the garnet group. Demantoid has diamond-like luster when faceted. It is the softest member of the garnet group, but relatively hard at 6.5 on the Mohs scale. The most-valuable gems have a rare “horsetail” inclusion that is highly prized by collectors. Sources include China, Madagascar, Namibia, and Russia.
Diamond is the only gemstone composed of a single element – carbon. It is also the hardest natural gem, holding the position of 10 on the Mohs scale. Diamond takes a fine polish, which makes its surfaces highly reflective. This type of luster is described as adamantine. Diamonds come in all colors of the rainbow. Those not represented on the normal diamond color-grading scale are known as fancies, the rarest being red diamond. Color in diamond is caused by structural irregularities, or trace elements. Notable sources of diamond include Russia, Botswana, Democratic Republic of the Congo, Australia, South Africa, Canada, and Angola.
Diopside is a gemstone that belongs to the pyroxene mineral group. It is best known for its rich-green variety, called chrome diopside. The name is an allusion to the chromium content responsible for the color. Another gemstone prized by collectors is black star diopside. This phenomenal variety exhibits four rays, each of which is bent, giving it a distinctive look. Sources for diopside include Austria, Finland, India, Madagascar, Myanmar (Burma), South Africa, Sri Lanka, and the United States.
The term druze, and its alternate spelling druse, describes a layer of crystals that form a mineral crust. The crust may be found on the surface of minerals or rocks, or as a lining on the interior cavity of a geode. The adjective used to describe this formation is druzy or drusy (druzy quartz, for example).
Emerald is the most-famous member of the beryl species. It is highly prized for its rich greens, which serve as a point of comparison for many other gemstones. The greens come in a variety of shades, often with secondary blue or yellow hue. Chromium and vanadium are the elements responsible for the coloration of emerald. Colombia is the most-famous source of emerald, but others include Afghanistan, Brazil, Madagascar, Pakistan, Nigeria, Russia, Zambia, and Zimbabwe.
The name fire opal is used to describe a yellowish to reddish variety that is found in North, Central, and South America. Fire opal ranges from transparent to translucent, and rarely displays play-of-color. Reddish material is commonly called cherry opal. Notable sources include Brazil, Guatemala, and Mexico.
Fluorite is a mineral that comes in a wide variety of colors. Because it is relatively soft, it is often carved into figurines, bowls, eggs, spheres, and various decorative objects. Multicolor gemstones are often cut from crystals, but individual colors can also be found.
Garnet is a group of colored minerals with a common crystal structure and similar (but not exact) chemical composition. Main garnet groups include pyrope, almandite, spessartite, grossularite, andradite, and uvarovite. On Mohs' scale of hardness, garnet ranks 6.5 to 7.5. This wide-ranging family of gemstones covers virtually every color and is found all around the world. Some varieties of garnet are quite common, while others are incredibly rare and among the most valuable colored gemstones on the market
Most gemstones are actually mineral crystals (except for non-mineral, organic gems like pearls, coral, and amber). Mineral crystals form through a naturally occurring combination of chemicals, heat, and/or pressure. These chemicals affect the shapes and colors of the resulting crystals. Most mineral crystals are tiny, but a few grow large enough to be cut into beautiful gemstones. The three characteristics that qualify a mineral crystal to be a gemstone and help determine its value are durability, beauty, and rarity.
Colorless beryl is known as goshenite. On Mohs' scale of hardness, goshenite ranks 7.5 to 8 and it has a vitreous luster. Primary goshenite sources include the United States (Goshen, Massachusetts), Brazil, China, Canada, Mexico, and Russia.
Literally meaning "shell," heishi (pronounced "hee-shee") is considered the most ancient jewelry form of New Mexico and has been linked to the Santo Domingo and San Felipe Pueblo Indians. Heishi originally referred to pieces of shell exquisitely crafted and strung on necklaces. Now it may also refer to small handmade beads of other materials.
Hessonite is a brownish-red variety of garnet.
Howlite, a calcium borosilicate hydroxide is a silicate mineral found in evaporive deposites. Howlite was discovered at Tick Canyon, California in 1868 by Henry How (1828 - 1879), a Canadian chemist, geologist, and mineralogist. In appearance, it is white with fine grey or black veins in an erratic, often web-like pattern, and is opaque with a sub-vitreous lustre. Its structure is monoclinic with a Mohs hardness of 3.5 and lacks regular cleavage. Howlite is commonly used to make decorative objects such as small carvings or jewelry components. Because of its porous texture, howlite can be easily dyed to imitate other minerals, especially turquoise because of the superficial similarity of the veining patterns. The dyed howlite (or magnesite) is marketed as turquenite. howlite is also sold in its natural state, sometimes under the misleading trade names of "white turquoise" or "white buffalo turquoise", or the derived name "white buffalo stone".
Indicolite (also indigolite) is a greenish blue to blue variety of tourmaline
Iolite is an iron magnesium aluminum silicate mineral that has gained popularity as a gemstone. It is primarily available in various shades of blue to violet-blue. Alternate names include dichroite and cordierite. Iolite crystallizes in the orthorhombic system and is highly pleochroic. Changes in color, or intensity of color can be seen when the stone is rotated and viewed at different angles. Iolite is moderately hard at 7 to 7.5 on the Mohs scale. Phenomena are rare, but chatoyancy and asterism are possible when inclusions of hematite or goethite are present and aligned properly. Iolite three carats or larger are difficult to find in any quantity. Gemstones over 10 carats are rare and highly prized by collectors. Notable sources of iolite include Brazil, India, Madagascar, Myanmar, Sri Lanka and Tanzania. Iolite is a gemstone with a slight variability in chemical composition between stones. It exhibits a blue-to-violet range of colors and sometimes shows a brownish streak. Iolite is pleochroic, meaning it can appear different colors from different directions--in this case, some combination of blue, violet blue, colorless, and brownish. On Mohs' scale of hardness, iolite is 7 to 7.5 and it has a greasy luster. Primary sources of iolite include Burma (Myanmar), Brazil, India, Madagascar, Sri Lanka, and the United States.
Called the stone of heaven, jade is a hard stone that has been treasured by the Chinese for over 7,000 years. Jade is actually a term that encompasses two different mineral species with similar appearance: nephrite and jadeite.
A fine-grained quartz, jasper is opaque and most commonly exhibits a brownish-red color, but it can also be green, yellow, brown, or black. On Mohs' scale of hardness, jasper ranks 6.5 to 7. Primary jasper sources include Egypt, Australia, Brazil, India, Canada, Kazakhstan, Madagascar, Russia, Uruguay, and the United States.
Kianga™ Tanzanite Like a dazzling whirlwind of magnificent light, Kianga™ tanzanite captures the essence of tanzanite’s awe-inspiring beauty and exotic grandeur. The name Kianga™, taken from the Swahili word for ‘burst of light’
Kunzite is a gemstone variety of spodumene. It is known for a range of pink-violet to light-violet colors, but has also been identified in canary yellow, colorless, brown, and greenish-violet. On Mohs' scale of hardness, kunzite ranks 6.5 to 7. It has a vitreous luster, and kunzite sources include Brazil (Minas Gerais), Afghanistan, Burma (Myanmar), Madagascar, Pakistan, and the United States.
Kutamani Tanzanit From the exotic east African country of Tanzania comes a rising new tanzanite star, Kutamani Tanzanite™. Named from the native Swahili language, Kutamani translates to “aspire”. While Kutamani Tanzanite™ has a fewer internal characteristics than our other tanzanite products, its regal, rich hues more than make up for their presence
Kyanite has a similar chemical composition to andalusite and fibrolite, but it has a different crystal structure. Kyanite exhibits a small range of colors including blue, colorless, blue-green, and brown. On Mohs' scale of hardness, kyanite ranks 4 to 4.5 and it has a vitreous luster. Primary kyanite sources include Burma (Myanmar), Brazil, Kenya, Austria, Switzerland, Zimbabwe, and the United States.
Labradorite is a gemstone in the feldspar family. It is known for a brilliant play of color and exhibits lustrous metallic tints of blue, green, yellow, red, gold, and purple. On Mohs' scale of hardness, labradorite is 6 to 6.5. It has a vitreous luster. Primary labradorite sources include Canada (Labrador, Newfoundland), Australia (New South Wales), Madagascar, Mexico, Russia, and the United States.
Lapis Lazuli is a complex composition of multiple minerals, which technically makes it a rock. Lapis exhibits a range of beautiful blues from azure blue to violet to greenish blue. On Mohs' scale of hardness, lapis lazuli is 5 to 6. It has a vitreous and greasy luster, and primary lapis sources include Chile, Russia, Afghanistan, Angola, Burma (Myanmar), Canada, Pakistan, and the United States (California, Colorado).
Most gemstones are actually mineral crystals (except for non-mineral, organic gems like pearls, coral, and amber). Mineral crystals form through a naturally occurring combination of chemicals, heat, and/or pressure. These chemicals affect the shapes and color of the crystals. Most mineral crystals are tiny, but a few are large enough to be cut into gemstones. The term "mineral crystal" usually refers to the mineral in its rough form, before it is cut into a gemstone.
Moldavite is a gemstone in the tektite group. It exhibits a bottle-green to brown-green color. On Mohs' scale of hardness, moldavite is 5.5. A natural glass, moldavite has a vitreous luster. Primary sources (and some other names for moldavite) include Australia (Australite), Borneo (Billitonite), the United States (Georgia, known as Georgiaite), Indochina (Inchinite), Java (Javaite), and the Philippines (Philippinite).
Mookaite jasper, also known as mookite, mookalite, mookerite, moakite, moukalite and moukaite. However, mookaite is considered the correct spelling and is named after the local area it comes from, Mooka Creek in the Kennedy Ranges near Gascoyne Junction which is about 100 miles inland from the coastal town of Carnarvon in Western Australia. Mookaite is found only in Australia and is actually a fossiliferous sedimentary rock & it is reasonably common to find cavities left by decomposed belemnite casts or in some rare cases , impressions of ammonites. (Windalia Radiolarite) Microscopic examination shows this rock consists of the remains of tiny organisms known as radiolaria that have an unusual skeletal structure of opaline silica. Billions of these little critters were deposited as sediment in the shallow areas of ancient sea beds. When the seas retreated, these sediments were cemented into solid rock by silica carried in groundwater. The type and degree of silicification varies from place to place, forming opalite, chert and chalcedony. It has been found in many very bright colors, reds, purples, tan, snow white, ivory white, pinks and many other shades. Sometimes but not often it will have black dendrites and in the hands of a careful lapidary the cabochons can be stunning especially if you get very lucky and run into a nice dendrite tree. The more scenic the more these cabochons will bring. A hundred dollars is common for a nice dendritic stone
Moonstone is a gemstone in the feldspar family. Moonstone exhibits a small range of colors including yellow, blue, colorless, and even pink, with or without a pale silver sheen. On Mohs' scale of hardness, moonstone is 6 to 6.5 and it has a vitreous luster. Primary sources include Sri Lanka, Burma (Myanmar), Brazil, India, Madagascar, and the United States.
Morganite is a gemstone in the beryl family. It exhibits a range of colors from soft pink to violet to salmon. On Mohs' scale of hardness, morganite is 7.5 to 8 and it has a vitreous luster. Primary sources include Afghanistan, Brazil, China, Madagascar, Mozambique, Namibia, Zimbabwe, and the United States (California, Utah).
MOTHER OF PEARL:
Mother of pearl is the pearl lining of an oyster or mollusk shell. Only oysters or mollusks that have this lining can produce pearls. This lining is also used as inlay in jewelry and other ornamental items
Opal is a unique gemstone that often displays a beautiful play-of-color. Opal exhibits all colors and both light and dark base colors that reflect a rainbow-like display of multiple colors when viewed from different angles (play-of-color). On Mohs' scale of hardness, opal ranks 5.5 to 6.5. Primary opal sources include Australia, Brazil, Guatemala, Honduras, Indonesia, Japan, Mexico, Russia, and the United States (Nevada, Idaho).
While most gemstones are minerals with an inner structure that result in crystal forms, a few gemstones (such as amber and pearl) are primarily non-mineral, being formed by plants and animals. Organic gemstones were, simply put, formed by once-living organisms like oysters, coral, or trees.
Literally the Sinhalese word meaning "lotus flower," padparadscha refers to a lush pinkish-orange sapphire.
Peridot is a gemstone in the olivine family. It exhibits a range of greens from yellow-green to olive green to brownish green. On Mohs' scale of hardness, peridot ranks 6.5 to 7. It displays a vitreous and oily luster. Primary peridot sources include Burma (Myanmar), Australia (Queensland), Brazil (Minas Gerais), China, Kenya, Mexico, Pakistan, Sri Lanka, South Africa, Tanzania, and the United States (Arizona).
Petalite is primarily a gemstone for collectors. It is often colorless, but there are also examples of pink and yellow varieties. On Mohs' scale of hardness, petalite is 6 to 6.5. It has a vitreous luster and sources include Western Australia, Brazil (Minas Gerais), Italy (Elba), Namibia, Sweden, Zimbabwe, and the United States.
Natural pyrite has a brassy appearance and is sometimes confused for gold, earning it the nickname "fool's gold." Used by jewelers for thousands of years, pyrite has been found in ancient Greek jewelry and the tombs of Incas. Marcasite jewelry is actually set with pyrite.
Pyrope is a variety of garnet. It usually exhibits a blood-red color but can also be tinged with yellow or purple. On Mohs' scale of hardness, pyrope ranks 7 to 7.5. It has a vitreous luster, and primary pyrope garnet sources include Burma (Myanmar), China, Madagascar, Sri Lanka, South Africa, Tanzania, and the United States (Arizona).
Quartz is one of the most common gem families and can be found all around the world. Quartz comprises several different groups of gems from crystalline quartz (crystals viewable by the naked eye) and cryptocrystalline (microscopic crystals). Crystalline quartz includes amethyst, aventurine, rock crystal, blue quartz, citrine, hawk's eye, prasiolite, quartz cat's-eye, smoky quartz, rose quartz, and tiger's eye. Cryptocrystalline quartz is also known as chalcedony and includes agate, bloodstone, carnelian, chrysoprase, jasper, moss agate, onyx, and sard.
Rhodolite is a variety of garnet. An intermediate stone between pyrope and almandine garnets, rhodolite exhibits a lovely rhododendron red color with a lively luster. On Mohs' scale of hardness, rhodolite ranks 7 to 7.5. It has a vitreous luster and primary sources include Burma (Myanmar), China, Madagascar, Sri Lanka, South Africa, Tanzania, and the United States.
Rhodonite is an ornamental translucent to opaque stone with a rose red color. It often resembles dark pink marble veined with black.
Rubellite is a gemstone variety of the tourmaline group. Valued for its ruby-red color, rubellite actually exhibits a specific range of colors from pink to red, sometimes with a violet tint. On Mohs' scale of hardness, rubellite ranks 7 to 7.5. Rubellite has a vitreous luster on crystal surfaces but a greasy luster on fractures. Rubellite sources include Brazil (Minas Gerais, Paraiba), Afghanistan, Australia, Burma (Myanmar), India, Madagascar, Malawi, Mozambique, Namibia, Nepal, Nigeria, Pakistan, Russia, Zambia, Zimbabwe, Sri Lanka, Tanzania, the United States (California, Maine), Zaire, Elba (Italy) and Switzerland (Tessin).
Ruby is a gemstone in the corundum family. It exhibits a range of red colors, and the most desired color is "pigeon's blood" red (pure red with just a hint of blue). On Mohs' scale of hardness, ruby ranks a hard 9. It has a strong, adamantine ("diamond-like") luster, and ruby sources include Burma (Myanmar), Thailand, Sri Lanka, Tanzania, Afghanistan, Cambodia, Kenya, Madagascar, and Vietnam
RUTILE- ECLIPSE STONE:
Rutile is a common accessory mineral in high-temperature and high-pressure metamorphic rocks and in igneous rocks. Rutile is the preferred polymorph of TiO2 in such environments because it has the lowest molecular volume of the three polymorphs; it is thus the primary titanium bearing phase in most high pressure metamorphic rocks, chiefly eclogites. Brookite and anatase are typical polymorphs of rutile formed by retrogression of metamorphic rutile. Within the igneous environment, rutile is a common accessory mineral in plutonic igneous rocks, although it is also found occasionally in extrusive igneous rocks, particularly those which have deep mantle sources such as kimberlites and lamproites. Anatase and brookite are found in the igneous environment particularly as products of autogenic alteration during the cooling of plutonic rocks; anatase is also found formed within placer deposits sourced from primary rutile. The occurrence of large specimen crystals is most common in pegmatites, skarns and particularly granite greisens. Rutile is found as an accessory mineral in some altered igneous rocks, and in certain gneisses and schists. In groups of acicular crystals it is frequently seen penetrating quartz as in the "fléches d'amour" from Graubünden, Switzerland. In 2005 the Republic of Sierra Leone in West Africa had a production capacity of 23% of the world's annual rutile supply
Sapphire is a gemstone in the corundum family. Known for its beautiful "cornflower blue" color, sapphire also comes in a wide range of colors. In fact, corundum comes in every color of the rainbow, and they are all sapphire--except red, which is ruby. On Mohs' scale of hardness, sapphire is a hard 9. It has a strong luster like diamonds, and sources include Australia, Burma (Myanmar), Sri Lanka, Thailand, Montana, Brazil, Cambodia, China, Kenya, Madagascar, Malawi, Nigeria, Pakistan, Rwanda, Tanzania, Vietnam, Zimbabwe, and the United States (Montana).
Scapolite is a distinctly fibrous gemstone. It is usually found in white, yellow, pink, and violet hues. On Mohs' scale of hardness, scapolite is 5.5 to 6. Scapolite has a vitreous luster, and sources include Burma (Myanmar), Brazil, Canada, Madagascar, and Tanzania.
Ornamental sodalite has a rich blue color and is sometimes mistaken for lapis.
Spessartite is a variety of garnet. The color ranges from a yellowish-orange to an intense aurora red to a deep orange color. On Mohs' scale of hardness, spessartite ranks 7 to 7.5. It has a vitreous luster, and primary sources include Burma (Myanmar), China, Madagascar, Sri Lanka, South Africa, Tanzania, and the United States.
Sphene is a brilliant transparent gemstone. It exhibits a range of colors from yellow to brown to green and even reddish. On Mohs' scale of hardness, sphene ranks 5 to 5.5. It has an adamantine luster, and sources include Burma (Myanmar), Brazil, Mexico, Austria, Sri Lanka, and the United States.
Sunstone, also known as aventurine feldspar, is a gemstone in the feldspar group. It normally has a rich golden or reddish-brown color with sparkling red and brown (and sometimes green or blue) inclusions that create a phenomenon known as aventurescence. On Mohs' scale of hardness, sunstone is 6 to 6.5. Sources include India, Canada, Madagascar, Norway, Russia (Siberia), and the United States (Oregon).
Tanzanite is a variety of zoisite. It has naturally occurring shades of blue, green, yellow, pink, brown, and khaki, but virtually all gem-quality crystals are heat treated to produce the highly valued shades of blue and blue-violet. On Mohs' scale of hardness, tanzanite is 6.5 to 7. So far, the single source of the world's tanzanite is in Tanzania near Arusha.
Tiger's eye (also called Tigers eye or Tiger eye) is a chatoyant gemstone that is usually a metamorphic rock that is a golden to red-brown color, with a silky luster. A member of the quartz group, it is a classic example of pseudomorphous replacement by silica of fibrous crocidolite (blue asbestos). An incompletely silicified blue variant is called Hawk's eye. The gems are usually cut en cabochon in order to best display their chatoyancy. Red stones are brought about through gentle heat treatment. Honey-colored stones have been used to imitate the much higher valued cat's eye chrysoberyl (cymophane), but the overall effect is unconvincing. Artificial fiberoptic glass is a common imitation of tiger's eye, and is produced in a wide range of colors. Tiger's Eye mostly comes from South Africa. Tiger iron is an altered rock composed chiefly of tiger's eye, red jasper, and black hematite. The undulating, contrasting bands of color and luster make for an attractive motif, and it is mainly used for jewelry-making and ornamentation. Tiger iron is a popular ornamental material used in a variety of applications, from beads and cabochons to knife hilts. Along with tiger's eye it is mined primarily in South Africa and Western Australia. Tiger's eye is primarily composed of silicon dioxide (SiO2) and is colored mainly by iron oxide. The specific gravity ranges from 2.64 -2.71 It is formed by the alteration of crocidolite.
Topaz is a gemstone found in vivid colors, including yellow, orange, reddish-brown, light to dark blue, pinkish-red, red, violet, light green, colorless, and can be treated to achieve unusual colors and effects known as mystic topaz. On Mohs' scale of hardness, topaz is 8. Topaz has a vitreous luster and sources include Brazil (Minas Gerais), Afghanistan, Australia, Burma (Myanmar), China, Japan, Madagascar, Mexico, Namibia, Nigeria, Pakistan, Russia (Urals, Transbaikalia), Zimbabwe, Sri Lanka, and the United States
Tourmaline is a fascinating mineral that can actually exhibit two or more colors in one crystal. Tourmaline possesses one of the widest color ranges, reproducing every conceivable color in a rainbow. On Mohs' scale of hardness, tourmaline is 7.5. It is vitreous on crystal surfaces and greasy on fractures. Sources of tourmaline include Brazil (Minas Gerais, Paraiba), Afghanistan, Australia, Burma (Myanmar), India, Madagascar, Malawi, Mozambique, Namibia, Nepal, Nigeria, Pakistan, Russia, Zambia, Zimbabwe, Sri Lanka, Tanzania, the United States (California, Maine), Zaire, Elba (Italy) and Switzerland (Tessin).
Tsavorite is one of the most valuable gemstones in the garnet family. Tsavorite exhibits a slightly yellowish green to emerald green color. On Mohs' scale of hardness, tsavorite is 7 to 7.5. It has a vitreous luster, and sources include Kenya and Tanzania.
Turquoise is a translucent to opaque gemstone. It exhibits a range of blue and green colors from sky-blue to blue-green to apple green. On Mohs' scale of hardness, turquoise ranks 5 to 6. Sources include Iran (near Nishapur), Afghanistan, Argentina, Australia, Brazil, China, Israel, Mexico, Tanzania, and the United States (Arizona, Nevada).
When discovered in the Dry Creek Mine (Note: not it's name today) in the Shoshone Indian Reservation near Battle Mountain, Nevada in 1993, they (the discoverers) were not sure what it was. Because of its hardness, it was decided to have it assayed. Their suspicious proved correct. It was, in fact, white turquoise. It was not until 1996, however, that it was finally made into jewelry. The Shoshone Indians are not known for jewelry work and, as a consequence, the Shoshone sell or trade the white turquoise to the Navaho in Arizona who work it into jewelry. Because white turquoise is as rare as the white buffalo, the Indians call it "White buffalo" turquoise. Turquoise gets its color from the heavy metals in the ground where it forms. Blue turquoise forms where there is copper present (most Arizona turquoise). Green turquoise forms where iron is present (most Nevada turquoise). White turquoise, where there are no heavy metals present, turns out to be rare. To date no other vein of white turquoise has been discovered anywhere else. When this current vein runs out that will be the last of it.
Lime colored Turquoise
is a rarity, it is caused from the lack of, or lesser amounts of copper and a pressence or zinc when it was being formed. Lime Green Turquoise is highly collected by Turquoise connoisseurs worldwide and it is truly beautiful! Lime Turquoise comes from several Nevada Mines, the main ones being the Tonopah Blue Gem mine, the Carico Lake mine, the Orvil Jack mine, the Pixie mine, and the Stennich Turquoise mine. Keep in mind, copper is one of the ingredients of Turquoise and if there is no copper, it is not Turquoise. There are two other minerals that run near Turquoise that have often been called Turquoise in the past, Calcociderite and Variscite. Both of these materials can be spectacular and beautiful, but, they are not Turquoise. Both Variscite and Chalcociderite are valueable and highly collectible. Both Gems run in a lime green color and are super rare in lime green
Yellow Turquoise is a jasper/serpentine stone with hematite webbing, rather than a true turquoise. It is said to be helpful for enhancing communication, intuition, and creativity. It is also used to bring wisdom particularly through meditation. Yellow Turquoise is said to increase serenity via balance, honesty, and an ability to adjust to changes in life. It is also used as a protection stone, that brings an increase of personal power and energy by protecting the same. It is considered a wonderful general healing stone by many. Yellow Turquoise is also said to bring positive energy and sensitivity. Yellow Turquoise is associated primarily with the solar plexus chakra but also is used to strengthen and align all the chakras.
Zircon is a beautiful, natural gemstone with a high refractive index and strong dispersion. Zircon should not be confused with cubic Zirconia, as the two are completely unrelated. Zircon exhibits a range of colors including yellow, brown, orange, red, violet, blue, green, and colorless. Blue zircon is usually heated, but only brownish zircon from Cambodia heats to that popular blue color. On Mohs' scale of hardness, zircon is 6.5 to 7 and it has a vitreous to brilliant luster. Zircon sources include Burma (Myanmar), Cambodia, Sri Lanka, Thailand, Australia, Brazil, Korea, Madagascar, Mozambique, Nigeria, Tanzania, and Vietnam
GLOSSARY OF STONES GEMS AND OTHER COMMON MATERIALS
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