Abalone 
Also known as Ear Shell, is found in waters off the coasts of California, South America, Japan, and China. 

Agate (see also Chalcedony) 
Agates occur in nodular masses in rocks such as volcanic lava. When split open, they have an amazing variety of patterns and colors. They have distinctive banding that separates them from other kinds of Chalcedony.
Found in Germany, Uruguay, Brazil, India, China, Mexico, Madagascar, Italy, Egypt, Scotland, and the USA.
Brown or black agates with a white ring in the center may be used to ward off the evil eye. 

Alexandrite 
A green form of Chrysoberyl.

Amazonite 
A green or blue-green member of the Feldspar family.

Amber 

Mohs Hardness: 1-1.2 - Treatment: None - Color: Golden yellow to orange 
Amber is fossilized resin of trees. Most amber is golden yellow to golden orange. Transparent to translucent it usually occurs as nodules or small, irregularly shaped masses, often with a cracked and weathered surface. Amber may contain insects, moss, lichen, or pine needles that were trapped millions of years ago while the resin was still sticky.
Found in the Baltic region of Poland and the former USSR. Amber has been found on the coasts of England, Norway, and Denmark. Other localities include the Dominican Republic, Mexico, France, Spain, Italy, Germany, Romania, Canada, Czechoslovakia, and the USA.
Amber talismans have been found in Stone Age archaeological deposits. Knock on wood three times with a natural piece of amber to ask the  trees spirits to grant you a wish. 

Amethyst 

Mohs Hardness: 7 - Treatment: None - Color: Light to medium purple (See Quartz) 
Amethyst is crystalline quartz in shades of purple, lilac, or mauve. Amethyst is Dichroic, showing a bluish or reddish purple tinge when viewed from different angles. Some amethyst is heat treated to change the color to yellow, producing citrine.
Found in Brazil, Russia, Canada, Sri Lanka, India, Uruguay, Madagascar, Germany, Austria, Namibia, Zambia, and the USA. 

Ametrine 
Crystals that are part citrine and part amethyst are called Ametrine.

Apatite
Deposits are found in Burma (Myanmar,) Brazil, India, Kenya, Madagascar, Mexico, Norway, Sri Lanka, South Africa, and the USA.
Apatite comes in a variety of colors ranging from yellow to green, white, pink, blue, or purple.

Aquamarine 
A blue-green stone. 

Aventurine  

Mohs Hardness: 7 - Treatment: None - Colors: Green, Blue, Raspberry
Discovered around 1700 and given the same name as a type of similar-looking glass Mostly dark green variety of mineral (usually quartz or feldspar) with metallic iridescence caused by included fuchsite (green mica) or red- to gold-brown caused by hematite leaves. Deposits are found in Brazil, India, Austria, Russia, and Tanzania.

Azurite
A dark blue, metallic mineral. 


Beryl 
An ore of beryllium. CLEAR BERYL- known as Goshenite GOLDEN BERYL-  known as Heliodor, PINK BERYL- known as Morganite or Bixbite. 

Black Onyx 

Mohs Hardness: 6.5-7 - Treatment: Dyed for color uniformity - Color: Black (See also Chalcedony) 
Onyx is similar to agate, but it has straight rather than curved bands. These may be brown and white or black and white. Since ancient Egyptian times, onyx has been stained to improve or change its color. Much onyx has been produced by soaking agate in a sugar solution, then heating it in sulfuric acid to carbonize the sugar particles.
Found worldwide. Onyx is formed by the deposition of silica in gas cavities in lava, which results in the distinctive bands.

Bloodstone (See also Chalcedony) 
Bloodstone is opaque, green, spotted varieties of chalcedony. The dark green of bloodstone is spotted with red because of the presence of iron oxides. These distinctive spots seem to resemble blood, thus giving the stone its name.
Found in India, Brazil, China, Australia, and the USA.
 During the Middle Ages, bloodstone was thought to have the power to bring rain. 

Botswana Agate (See Agate) 
A banded agate 

Calcite  
The various crystallized forms of calcite include masses, grains, stalactites, scalenohdrons, and rhombohedrons. It is, however, characterized by the rhombohedron crystallization. Calcite is colourless or white and can become green, pink, peach, golden, orange, yellow, red, blue, grey, or black when other compounds blend with it during formation. 

Carnelian  

Mohs Hardness: 6.5 - Treatment: usually heat treated - Color: Light to dark reddish brown/orange (See also Chalcedony) 
Carnelian is also called cornelian, a translucent, reddish orange variety of chalcedony. Its various shades of red are due to the presence of iron oxide. Stones may be uniformly colored or faintly banded.
The best carnelian is from India, where it is placed in the sun to change brown tints to red. Although most carnelian on the market is stained chalcedony from Brazil or Uruguay.
 

Chalcedony 

Mohs Hardness: 7 
White to gray, brown, blue, black; clear read to brownish red (Carnelian); bright green with red spots (Bloodstone); variegated and banded (Agate); with moss like or treelike inclusions (Moss Agate); apple-green (Chrysoprase); variegated and mottled red, yellow, brown (Jasper); whitish, dull gray, smoky brown to black (Flint) 
Chalcedony is a form of quartz crystal. During the 1700's it was believed that chalcedony embodied the power to banish evil spirits and nightmares. Chalcedony was once carried by sailors to protect against drowning.
There are many varieties of chalcedony crystal- Agate, Bloodstone, Carnelian, Chrysoprase, Fire Agate, Fortification Agate, Flint, Jasper, Landscape Agate, Moss Agate, Onyx, Prase. 

Charoite (New to the Market) 
Lilac-colored to violet. Translucent to opaque. Named after a river in Siberia, Russia. Was recognized in 1978 as independent mineral.
Found in Russia.
"new to the market" does not necessarily mean that this stone has not been around for a long time, but its importance for the gemstone trade has remained minor or insignificant due to its extreme rarity of occurrence in gemstone quality or because it has been poorly marketed. 

Chrysolite 
Historically associated with repelling the "Evil Eye." 

Chrysocolla 
A blue-green member of the quartz family. Also known as Gem Silica. 

Chrysoprase 

Mohs Hardness: 6.5 - Treatment: None - Color: Bottle green (See also Chalcedony) 
Chrysoprase/Prase was used by both the Greeks and Romans as a decorative stone. It is the most valued variety of chalcedony. The color, derived from the presence of nickel, may fade in sunlight, and stones may then be confused with fine jade.
Found in Poland, Czechoslovakia, Australia, Brazil, Urals (Russia), Austria, and California in the USA.
One Myth states that if a Chrysoprase crystal is held in the mouth it gives the power of invisibility. 

Citrine - 

Mohs Hardness: 7 - Treatment: usually heat treated - Color: Medium to dark gold; some color zoning (See also Quartz) 
Citrine is the yellow or golden yellow variety of quartz. The yellow coloration, due to the presence of iron, is also responsible for the name, derived from the word citrus. natural citrine is usually a pale yellow, but rare; most citrine is a heat-treated amethyst. 
Found in Brazil, Spain, Madagascar and the former USSR. 
Citrine was a prized stone among the Celtic and Scottish people. 

Coral - 

Mohs Hardness: 3-4 
Is formed from the skeletons of tiny sea creatures. 
BLACK CORAL -The black coral used in making jewelry comes from the Red Sea off the coast of Jeddah, Saudi Arabia. It was taken from a depth of 75 - 100 feet below the surface of the sea. This batch of coral comes from an area which is located 25 kilometers north of Jeddah. Several phases of curing and polishing take place before it is used in making jewelry. It is durable if properly taken care of. You can clean the black coral jewelry with any cleaner that is safe to use on pearls. Keep the coral away from harsh chemicals and chlorine in swimming pools. If you properly care for your black coral, it will last a lifetime. In old days black coral was only allowed to be worn by the kings and was thought to bring good luck (thus it was known as Kings Coral) 

Crazy-lace Agate (See Agate) 

Dichroic Glass
"Dichroic" is defined as the property of having more than one color, especially when viewed from different angles. Dichroic glass is a high-tech spin-off of the space industry. Thin layers of metallic oxides, such as titanium, silicon, and magnesium are deposited upon the surface of the glass in a high temperature, vacuum furnace. 

Dioptase
Crystallizes forming emerald-green masses, prismatic crystals, and crystalline aggregates. It is a relatively rare mineral and is found in only a few localities. The most beautiful dioptase comes from Tsumeb, Namibia. 

Dolomite 

Druse or Drusy 
Crust of tiny crystals lining a rock cavity. These are minerals with their crystal structure exposed, like the inside of a geode on a smaller scale. Often, Drusy stones exhibit more richness of color than their composite mineral. 

Dumortierite 
Dumortierite is best known in its massive form. which makes an attractive violet and blue decorative stone when polished. Dumortierite is also found inter grown with rock crystal (colorless quartz) and is then called Dumortierite quartz. This material is usually cut or polished to make decorative stones and beads.
Found mostly in Nevada, USA - other areas include France, Madagascar, Norway, Sri Lanka, Canada, Poland, Namibia, and Italy.
Dark blue, violet blue or reddish brown.  
Dumortierite was named after the French scientist M. E. Dumortier. 

Emerald - 

Mohs Hardness: 7.5 - Treatment: Oiled - Color: Light to medium green 
Emerald gets its name from the Latin smaragdus, which refers to a type of precious gemstone. Traces of chromium and vanadium in the crystalline structure produce the green color. 
Emerald has been treasured since 4000 B.C., when it was traded in early gem markets of Babylon. Egyptian emerald mines were worked as early as 2000 B.C. and were the main source of emeralds for the West until the 16th century. By this time finer-quality emeralds were being mined in Colombia, and eventually became the world's most coveted emeralds. 
A green member of the Beryl family. 

Fire Agate 
Occurs due to the inclusion of very thin layers of iridescent limonite. 

Fire Opal- see Opal

Fluorite 
Fluorite has limited use as a gemstone because it is relatively soft and easily scratched. Despite its fragility, stones are faceted and can be polished very brightly.
Found in Canada, South Africa, Thailand, Peru, Mexico, China, Poland, Hungary, Czechoslovakia, Norway, England, Germany, Switzerland, and the USA.
Ancient Egyptians used fluorite in statues and to carve scarabs and the Chinese have used it in carvings for more than 300 years.

Fossil 
The fossil is a preserved remnant of the past. Most fossils are organic matters that have transformed to stone, in many cases a mineral.

Garnet 

Mohs Hardness: 7-7.5 - Treatment: None - Color: Blood red to brownish plum to black to green 
Deep red to reddish black. Some Asiatic tribes once used garnets as bullets, believing that the red stone would cause a more deadly wound than a leaden bullet. An ancient Greco-Roman tradition claims that when engraved with the image of a dragon and worn as a talisman, the garnet brings riches, joy, and good health.
Found in South Africa, Argentina, Australia, Brazil, Myanmar, Scotland, Switzerland, Tanzania, and the USA (Arizona).

Gaspeite
Light green. Opaque.

Gold Vermeil 
Is gold electroplated over sterling silver. 

Golden Agate (see Agate) click on icon to take you there. 
Green Prase (see Chrysoprase) 

Hematite  

Mohs Hardness: 6-6.5 - Treatment: None - Color: Blackish grey with a metallic lustre 
Used as an ornamental stone since early times, hematite has sometimes erroneously been called black diamond. The ancient Egyptians used it to treat hysteria, to reduce inflammation and to place in tombs. Engraved hematite seals have been found in the ruins of ancient Babylon. 
Hematite usually occurs as massive, opaque material with a metallic luster, showing a blood red color when cut into thin slices.
Found around Lake Superior, Canada (Quebec), Brazil, Venezuela, England, Switzerland, Germany, and Elba.
Powdered, it may be used as an artist's pigment or for polishing. In the past it was worn as protection against bleeding. 

Hicorite (Moukaite) - see Jasper 
Hicorite is a trade name given to Moukaite (Jasper) - Pink to light red, cloudy. Found in Australia. 

Howlite 
Howlite crystallizes in the form of white nodules, compact masses, and tabular crystals.

Iolite 

Mohs Hardness: 7-7.5 - Treatment: None - Color: Violet blue  - also known as Cordierite
Iolite crystallizes in the form of masses, grains, and short prismatic crystals. The color range includes blue, brown, yellow, dark violet, grey, and green. This mineral also exhibits the pleochroic qualities; i.e., X-axis showing clear yellow, Y-axis showing dark violet, blue, or brown, and the Z-axis showing clear blue. In some cases a metamorphic change has occurred in the iolite and the colors which are seen are shades of grey-green, green-grey, and brown-grey. Iolite is called the "violet stone" 

Jade 

Mohs Hardness: 6.5-7 Treatment: None - Color: Soft to medium mint green to Dark green (Jadeite - Nephrite) 
For centuries, jade was thought to be a single gemstone, but in 1863 two types were recognized: jadeite and nephrite. Nephrite is more common, but both are tough, fine-grained rocks, suitable for carving.
Jadeite is found in Myanmar, Guatemala, Japan, Burma, and the USA (California) Nephrite is found in Turkistan, Central Asia, Myanmar, Siberia, Russia, China, New Zealand, Australia, USA, Canada, Mexico, Brazil, Taiwan, Zimbabwe, Italy, Poland, Germany, and Switzerland.
The Spanish conquistadors adopted the use of jadeite when they invaded Central America, and often wore amulets made from it. Jadeite has been said to be the magical stone of Xiuhtecuhtli, the Aztec god of fire. It was also a favorite body-piercing stone of the indigenous inhabitants of Brazil and the West Indies, and highly prized as a remedy by Egyptian healers. Ax heads and other tools of jade have been found in archeological sites throughout the world.

Jasper

various names and colors (See also Chalcedony) 
Jasper is a massive, fine-grained, opaque variety of chalcedony, believed to protect against sight defects and drought. It occurs in shades of brown, grayish blue, red, yellow, and green and mixtures of these.
Found in India, Venezuela, Russia, France, Germany, and in the USA

Jet 
Jet is organic in origin. Like coal, it was formed from the remains of wood immersed in stagnant water millions of years ago, then compacted and fossilized by the pressures of burial. Jet is black or dark brown but may contain pyrite inclusions, which have a brassy color and metallic luster. Jet takes a good polish and is often faceted. When burned or touched with a hot needle, it exudes the characteristic smell of coal.
Found in England, Spain, France, Germany, Poland, India, Turkey, the former USSR, China and the USA
Jet was popular for mourning jewelry in the 19th century because of its somber color and modest appearance, and it has been traditionally fashioned into rosaries for monks. Jet has also been known as black amber, as it may induce an electric charge like that of amber when rubbed. Powdered jet added to water or wine was believed to have medicinal powers.