Gemstone Glossary

African Opal - African opal is not fine gem quality opal and doesn't have the translucent fire of other opals. It is generally beige with darker beige or brown. African green opal is a rich green and brown stone.

Agate - Agate is a variety of chalcedony, and is banded. It comes in many colors and is often dyed or heat treated. When dyed the banding is not seen. Some of the agates are further described on this page.

Amazonite - A stone which has colorations in the aqua range and gets its name from the Amazon river. Some deeper toned and vivid forms of the stone can be confused with turquoise. Some amazonite has darker banding or dark flecks.

Amethyst - Amethyst is purple quartz and may range in color from lavender to deep purple. When heat treated it is called citrine.

Aquamarine - This stone is a type of beryl that is blue to blue green. It is most often heat treated to remove yellowness. It can be clear, translucent or have a cloudy appearance.

Aventurine - A hard stone with a lot of quartz, it is semi transparent. May be found in green or shades of red and orange.

Azurite - Azurite is a beautiful deep blue stone tending toward "azure" blue in color. The stone isn't very hard and is often coated with wax to give it a sheen. It is very often found with malachite, a green stone.

Black Onyx - Usually this stone has been dyed black. In nature onyx is banded and can be dark brown. Most likely the black onyx is actually dark brown onyx that has been dyed black to give it a dark, even color. This is an opaque stone of medium hardness.

Blue Lace Agate - This stone is usually pale blue to lavender in color and gently banded. It has a hard shiny appearance.

Blue Mist Chalcedony - Chalcedony is a quartz type stone and translucent. Blue Mist, like the name has a strong bluish cast which may range from blue-green to almost lavender. It also can be very pale, almost white.

Carnelian - Carnelian is a stone that gets its red to orange look because of its high iron content. The color ranges from light brownish red to deep transparent red. It has a medium hardness. Carnelian is often heat treated and may be dyed.

Chrysoprase - This is a form of chalcedony and is generally translucent blue green. There is also a variety called lemon chrysoprase which is a pale yellow stone that isn't as translucent.

Citrine - Citrine is a form of yellow quartz and is usually heat treated to get the color, which ranges from pale yellow to deep amber.

Crazy Lace Agate - This agate features crazy patterns in bright colors. Many times shades of red, gold and gray on a pale background. This is a very unusual looking type of agate. It can have shades of lavender and purple or can be in darker warm tones.

Fire Agate - Fire agate is named because the appearance resembles flames. It usually is the typical orange and cream coloration but may contain purple. It has an interesting look when cut a certain way that accentuates the "flame" look.