Compliments of
The International Gem Society
FACTS ABOUT GEMS
1. ALEXANDRITE : A member of the Chrysoberyl family, alexandrite holds a prized and highly priced position among jewelry and gem collectors. A color change stone, alexandrite can appear green in daylight and change to a raspberry color in incandescent light, but other color changes are also highly prized.
2. AMETHYST : Is one of the most prized and most interesting members of the quartz family. Ancient Romans believed that if one drank amethysts with their wine, they would not become inebriated, and many of the small goblets from that era are made from amethysts. Valued by the ancient Egyptians, the Hebrews and even the Christian Church, amethyst has played a key role in cultures throughout history.
3. ANDALUSITE : The variety chiastolite commonly contains dark inclusions of carbon or clay which form an X or a cross in section. Faceted andalusite stones give a play of red, green, and yellow colors that resembles a muted form of iridescence, although the colors are actually the result of unusually strong pleochroism.
4. APATITE : Apatite is not well known by the general public but is a frequently sought after choice for collectors. The astonishingly bright blue varieties attract attention for their amazing intensity. They almost seem to be lit from inside and thrill consumers. The apatite collector can enjoy a wide range of colors to complete their collection. Apatite is a naturally occurring beautiful gemstone. While it is known for its asparagus green hues, apatite actually can be found in a wide variety of colors ranging from colorless to pink, yellow, blue and violet. On Mohs’ scale of hardness, apatite is 5. Apatite has a vitreous luster and primary sources include Burma (Myanmar), Brazil, India, Kenya, Madagascar, Mexico, Norway, Sri Lanka, South Africa and the United States.
5. AQUAMARINE : Aqua means water, marine means blue in latin. Capture the vibrant blues of the sea in a stone and you have Aquamarine. From light blue to bluish green to deep blue, Aquamarine offers irresistible ranges of sea blue colors. A member of the beryl family (also known for emeralds), Aquamarine was referred to as sea-green beryl in ancient texts. American consumers have a very refined taste for aquas preferring the cool bluish tones. Many Europeans, including English, still prefer the greenish-blue (sea foam) variety. The two most important sources for Aquamarine are Brazil and Africa.
6. CITRINE :is any quartz crystal or cluster that is yellow or orange in color. Although often cut as a gemstone, citrine is actually somewhat rare in nature. Most citrines on the market have been heat treated. Specimens of low grade, inexpensive amethyst or smoky quartz are often cooked at high temperatures to produce the more profitable orange yellow citrine. Citrines whose colors have been produced by artificial means tend to have much more of an orange or reddish caste than those found in nature, which are usually a pale yellow. Much of the natural citrine may have started out as amethyst but heat from nearby magmatic bodies may have caused the change to citrine. Citrine made by heating amethyst may be returned to a purple color by bombarding it with beta radiation. Interestingly, a popular gemstone on the market is a mixture of half amethyst and half citrine and is given the name ametrine, made by heating an amethyst until it turns into citrine, then irradiating a part of the resulting crystal or gemstone to convert that portion back to amethyst.
7. EMERALD : The most precious member of the Beryl family; emerald exhibits a distinct and recognizable pure green hue. This glorious stone was traded in one of the earliest known gem markets in Babylon around 4000 B.C. According to legend, the Emperor Nero watched the gladiator fights through an emerald. The world’s finest emeralds are found in the Andes of Colombia. Despite a 300-year search, no other deposit has rivaled the glory of the Colombian deposits. Emeralds are created with interesting and distinct identifiable “jardin” inclusions, which are particular to that beryl and are one of the most immediate ways of recognizing a genuine natural emerald.
8. IOLITE : is a clean, beautiful stone that is still very affordable. It can be found in blue to purple to light gray colors.
The Vikings used iolite as a light polarizer, using it to see through the haze and determine the exact location of the sun on overcast days.
With a very strong pleochroism, iolite changes colors when viewed from different angles. Iolite is found in Myanmar (previously called Burma), Brazil, India, Madagascar, Sri Lanka, and the United States.
9. KUNZITE : is a pink to lilac colored gemstone, a variety of spodumene with the color coming from minor to trace amounts of manganese. Some (but not all) kunzite used for gemstones has been heated to enhance its color. It was named in honor of New York mineralogist and gemologist George Frederick Kunz. It has been found in Brazil, USA, Canada, CIS, Mexico, Sweden, Western Australia, Afghanistan and Pakistan. SPODUMENE : is a pyroxene mineral consisting of lithium aluminium inosilicate - LiAl(SiO3)2 - and is a source of lithium. It occurs as colorless to yellowish, purplish or lilac kunzite (see below), yellowish-green or emerald-green hiddenite, prismatic crystals, often of great size. Single crystals of 14.3m in size are reported from the Black Hills of South Dakota.[1]
Crystals form in the monoclinic system and are typically heavily striated parallel to the principal axis. Crystal faces are often etched and pitted with triangular markings. Spodumene is derived from the Greek spodumenos (??????????), meaning "burnt to ashes," owing to the opaque, ash-grey appearance of material refined for use in industry. Spodumene occurs in lithium rich granites and pegmatites. Transparent material has long been used as a gemstone with varieties kunzite and hiddenite noted for their strong pleochroism. Source localities include Brazil, Madagascar, USA (North Carolina, California), Afghanistan, and Pakistan.
10. LABRADORITE : A member of the feldspar family, labradorite is a gray black or brownish stone with stunning flashes of blue, green and even yellow colors. Labradorite is named after the peninsula of Labrador in Canada. Sources for labradorite include Canada, Australia, Madagascar, Mexico, Russia and the United States.
11. MOONSTONE : From colorless to white to yellow, moonstone displays a floating blue, white or rainbow shimmering glow.
The glowing sheen actually results from interplay of light with layers of tiny albite crystals known as “adularescence.”
The rage in Europe, moonstone is growing in popularity in American and is fast becoming the most popular gem in the feldspar family.
Hindus considered moonstone sacred and ancient Romans believed the inner glow waxed and waned according to the cycles of the moon.
The finest moonstone comes from Myanmar and Sri Lanka.
12. MORGANITE : Named after the wealthy banker and gem lover J.P. Morgan, morganite is actually pink, rose, or peach beryl.
Pliny the Elder recommended beryl as an exceptional cure for eye diseases. Considered an oracle stone, beryl was once considered useful in divining the future and in look for missing items. A pure pink beryl is found in Minas Gerais (Brazil). Other sources include Afghanistan, China, Madagascar, Mozambique, Namibia, Zimbabwe, and the United States (Utah, California).
13. OPAL : Distinguished for its play-of-color, opal displays a brilliant range of rainbow-like colors when seen from different angles.
Opal was once considered a symbol of fidelity, assurance, and religious devotion. The ancient Roman historian, Pliny the Elder, suggested the opal is difficult to describe because it blends so many colors in a “brightness that is incredible.” Australia is the primary source of Opal. Opal is the birthstone for October.
14. PETALITE : Primarily a collector’s piece, petalite crystals are rare and somewhat brittle due to its perfect cleavage.
Its vitreous luster gives it a glassy appearance with a pearly luster on cleavage planes. Petalite occurs in Western Australia, Brazil, Italy, Namibia, Sweden, Zimbabwe, and the United States.
15. PRASIOLITE : Green-quartz or vermarine is a green-colored form of quartz, usually produced by artificially heat-treating amethyst. Since 1950, almost all has come from one small mine in Brazil. Natural prasiolite has also been observed in Lower Silesia in Poland. The gem has a refractive index of about 1.54-1.553. This material is occasionally referred to as "green amethyst" which is considered a misnomer by gemologists.
16. QUARTZ : The name "quartz" comes from the German "Quarz", which is of Slavic origin (Czech miners called it k?emen). Other sources insist the name is from the Saxon word "Querkluftertz", meaning cross-vein ore. Quartz is the most common material identified as the mystical substance maban in Australian Aboriginal mythology. It is found regularly in passage tomb cemeteries in Europe in a burial context, eg. Newgrange or Carrowmore in Ireland. The Irish word for quartz is grian cloch, which means 'stone of the sun'.
Roman naturalist Pliny the Elder believed quartz to be water ice, permanently frozen after great lengths of time. (The word "crystal" comes from the Greek word for ice.) He supported this idea by saying that quartz is found near glaciers in the Alps, but not on volcanic mountains, and that large quartz crystals were fashioned into spheres to cool the hands.
17. RHODOLITE : Is a varietal name for rose-pink to red mineral pyrope, a species in the garnet group. It is found in Cowee Valley, Macon County, North Carolina. The name is derived from the Greek for "rose-like", in common with many pink mineral types (e.g. rhodochrosite, rhodonite), but rhodolite itself is not officially recognised as a mineralogical term. This colouration, and the commonly inclusion-free nature of garnet from this locality, has led to rhodolite being used as a semi-precious gemstone. Chemically, rhodolite is an iron-magnesium-aluminium silicate, part of the pyrope-almandine solid-solution series, with an approximate garnet composition of Py70Al30.
18. RUBELITE : Red to pink colors of tourmaline are often referred to as rubellite.
Perfect for everyday wear, tourmaline is fairly durable at 7.5 on the Mohs’ scale and has no cleavage (reducing breakage and chipping).
Sometimes referred to as the “electric stone,” tourmaline becomes statically charged when heated or rubbed, attracting dust, lint and small pieces of paper. Tourmaline possesses one of the widest color ranges, reproducing every conceivable color in the universe.
Brazil stands as the most important supplier of tourmaline.
19. RUBY : This prized gemstone has been considered the foremost precious gemstone throughout history.
A well-cut ruby can approach the brilliant luster of a diamond. Some of the most famous rubies in the world are star rubies which have needle like inclusions. They are cut en cabochon to display the crossing 6 rayed stars. The finest rubies in the world are hidden in the remote valley of Mogok in Upper Burma, between India and China. Ruby comes from ruber, Latin for red, and describes the purest beauty of red imaginable. Some of the ancient Sanskrit names for ruby can be translated as “king of precious stones,” “leader of precious stones,” and “red as the lotus.”
20. SAPPHIRE : The name sapphire may derive from the Greek Sanskrit sanipriya, meaning “dear to the planet Saturn.”
Sapphire appears in a rainbow range of breathtaking hues. Most expensive and sought after fancy color of sapphire might be the padparadscha sapphire. Padparadscha means lotus blossom in a Malaysian language---and is the color of these beautiful peach-orangey-pink stones. Due to its hardness, brilliance and variety, some experts consider Sapphire to be the most important and most versatile of the gem families. Some of the most desired sapphires come from Kashmir, India.
21. SPESSARTITE : Malum granatum, Latin for garnet, refers to red pomegranate seeds. Found in many parts of the world and in a wide range of colors, garnet is a popular and exciting gemstone family. Spessartite is a rare garnet ranging from a yellowish-orange to an intense fiery orange known as mandarin garnet. Spessartite is a brilliant transparent gemstone. The colors of spessartite garnets can range from a bright vibrant orange to a deep red-orange color, and even some brownish and greenish oranges. Spessartite was once just a collector's gem but moved into mainstream gemology in the 1990s. Spessartite is 6.5 to 7.5 on the Mohs' scale of hardness and, like all garnet, is untreated, so the beautiful color that you see is strictly as nature created it.
22. SPINEL : Some of the most famous rubies in history are actually red spinel. As one of nature’s rare beauties, spinel is one of the few gems currently not enhanced or treated. Its durability and beauty make spinel the ideal gemstone for jewelry and gemstone collections.
According to legend, a red spinel actually saved the life of King Henry V. Spinel is commonly found with ruby and Spinel deposits in Burma, Sri Lanka, and Cambodia.
23. SUNSTONE : Is a gemstone in the feldspar group that exhibits schiller or sheen.
Sunstone is about 6 to 6.5 hardness on Mohs’ scale. Sources for the best sunstone include Tvedestrand and Hitero on the South Coast of Norway.
24. TANZANITE : The mineral zoisite was discovered around 1805 in the Austrian area by a Baron for whom it was named. It was usually brown in color, often nearly opaque. The discovery by accident of the tanzanite version, in the late 1960's was a great surprise in Tanzania Africa, where it was first thought to be sapphire crystals. The name Tanzanite was coined by Tiffany who had first and exclusive rights to the pretty blue violet mineral for many years. Wearing a well-cut Tanzanite communicates self-confidence, individuality, and maturity. Its brilliant color and its exclusive origin in Tanzania combine to make Tanzanite a unique and highly sought after gemstone. Tanzanite is a variety of zoisite. It has naturally occurring shades of blue, green, yellow, pink, brown and khaki but virtually all gemstone quality crystals are heat treated to produce the highly valued shades of sapphire blue, amethyst and blue violet. On Mohs’ scale of hardness, tanzanite is 6.5-7. The prime source of all the world’s tanzanite is in Tanzania near Arusha.
Color
Tanzanite has naturally occurring shades of blue, green, yellow, pink, brown and khaki but virtually all gemstone quality crystals are heat treated to produce the highly valued shades of sapphire blue, amethyst and blue violet.
25. TOPAZ : Is a silicate mineral of aluminium and fluorine with the chemical formula Al2SiO4(F,OH)2. It crystallizes in the orthorhombic system and its crystals are mostly prismatic terminated by pyramidal and other faces, the basal pinacoid often being present. It has an easy and perfect basal cleavage, meaning that gemstones or other fine specimens have to be handled with care to avoid developing cleavage flaws. The fracture is conchoidal to uneven. Topaz has a hardness of 8, a specific gravity of 3.4–3.6, and a vitreous luster. Pure topaz is transparent but is usually tinted by impurities; typical topaz is wine or straw-yellow. They may also be white, gray, green, blue, pink or reddish-yellow and transparent or translucent. When heated, yellow topaz often becomes reddish-pink. Topaz can also be irradiated, turning the stone blue, ranging from a light pure color to very dark almost electric blue. A recent trend in jewelry is the manufacture of topaz specimens that display iridescent colors, by applying a thin layer of titanium oxide via physical vapor deposition, this stone is then sold as 'mystic topaz'. Topaz is commonly associated with silicic igneous rocks of the granite and rhyolite type. It typically crystallizes in granitic pegmatites or in vapor cavities in rhyolite lava flows like those at Topaz Mountain in western Utah. It may be found with fluorite and cassiterite. It can be found in the Ural and Ilmen mountains, Afghanistan, Czech Republic, Germany, Norway, Pakistan, Italy, Sweden, Japan, Brazil, Mexico, and the United States.Topaz crystals from Brazilian pegmatites are up to 80cm x 60cm x 60cm in size. The biggest topaz crystal ever found, named "El Dorado", was found in Brazil in 1984. It weighs 6.2 kg and belongs to the British Royal Collection. Etymology and historical and mythical usage The name "topaz" is derived from the Greek tòpazi[òs], which was the name of an island in the Red Sea that was difficult to find.
26. TOURMALINE : Is a fascinating mineral that can sometimes exhibit two or more colors. It is 7.5 on the Mohs??? scale and has no cleavage, making it suitable for many types of jewelry use. Sometimes referred to as the “electric stone,” tourmaline becomes statically charged when heated or rubbed, attracting dust, lint and small pieces of paper. Tourmaline possesses one of the widest color ranges, reproducing every conceivable color in the universe. Tourmaline is fairly hard and durable, making it very wearable and an ideal gem for jewelry.
