Abalone - a mollusk with a pearly shell

Agate - a variety of chalcedony found in all colors

Amazonite - an opaque form of feldspar

Amber - the fossilized resin of prehistoric pine trees which ranges in color from golden to orange-red

Amethyst - a variety of quartz found in Brazil and Africa. Colors vary from deep purple to a bluish-violet color.

Ametrine - a crystal quartz that contains amethyst and citrine.  It is a bi-color gemstone including the violet of amethyst and the yellow of citrine.  Mainly found in Bolivia.

Andalusite - a naturally occurring pleochroic gemstone. Different colors appear as it is rotated including olive green, reddish brown, or grayish green.

Apatite - a naturally occuring gemstone first known for its asparagus green hues, can now be found in colors from colorless to pink, yellow, blue and violet.

Aquamarine - a form of beryl found in pale green blue to clear blue colors.

Baguette - gemstone cut in the shape of a narrow rectangle.

Beryl - a silicate mineral in several varieties such as emerald, aquamarine, and morganite.

Bezel -  gemstone setting where a strip or wall of metal encircles the gemstone.

Biwa Pearl - a freshwater cultured pearl from Japan.

Bloodstone -  a member of the chalcedony family, a deep green stone with red spots that resemble blood

Blue Lace Agate - Blue Lace is one of the most prized agates and has been hard to find lately. The best Blue Lace Agate comes from Namibia .

Botswana Agate - A variety of agate from Botswana, banded with fine, parallel lines, often colored pink blending into      white.

Briolette - a teardrop shaped stone faceted with triangular or rectangular facets, also know as drop cut

Cabochon - stone with a smooth carved surface, domed and unfaceted with a flat base

Carnelian - a quartz crystal and a sub-variety of chalcedony.  It can be found in colors ranging in flesh-color to reddish brown to a solid red.  Primarily found in Brazil, India, and Uruguay.

Chalcedony - a quartz, grayish-blue in color

Chrysoberyl - a semi-precious stone of transparent golden yellow, green yellow or brown.

Chrysoprase - apple-green chalcedony.

Citrine - a variety of quartz found in a range of colors from light yellow to red-orange to almost brown.

Cloisonné - the technique of enameling in which enamels are contained in cells of metal.

Coral - the skeleton of small marine animals, found in colors ranging from white to pink to red.

Crystal - containing a minimum of 10% lead oxide, known for its brillance.

Facet - a flat surface ground or cut and polished on the surface of a gemstone.

Feldspar - a group of minerals that play a part in the formation of rocks.  Found is stone varieties such as moonstone and sunstone.

Freshwater Pearl - pearls found in river mussels.

Garnet - A semi-precious stone found in many colors. Bohemian garnet is blood red; almandine ranges from deep red to deep purple; hessonite garnets are brown orange; and demantoid garnets are found in shades of green.

Hematite - an opaque mineral of iron oxide, ranging in color from deep grey to black metallic.

Hessonite - a brown red variety of garnet

Jet - fossilized coal, also called Whitby jet for the area of England where much of it came from or black jet.

Millefiori - glass ornamentation made from canes of colored glass that are layered and sliced to form patterns.

Mother of Pearl (MOP) - the smooth iridescent lining of the shells of certain mollusks.

Opal - a semi-precious stone with a rainbow-like iridescence which a categorized as three types:  opalescent; yellow-red fire; and the common opal.

Rondelle - a pierced piece of gemstone strung between the beads in a necklace.

Sardonyx - A type of Onyx. The layers in these stones range from translucent to opaque for sardonyx. The stones vary in color, too. They may be white or gray, ranging to many colorful varieties. Sardonyx stones usually contain flat-banded, white and brownish-red bands. Onyx is a gemstone with alternating light and dark bands, which are colored in brown, red, black, white and grey.

Spessartite - a variety of garnet whose color ranges from yellowish-orange to an intense red to a deep orange color.

Tiger Eye - Tiger eye is quartz that contains oriented fibers of crocidolite that have been replaced by silica.
 

Tiger Iron - Tiger iron is an altered rock composed chiefly of tiger's eye, red jasper and black hematite.

Tsavorite - an emerald green to green colored garnet.