Although the corundum group is most famous for red ruby and blue sapphire, gem-quality corundum can occur in a wide variety of colors, including colorless, yellow, green, pink and purple. Next to diamond, corundum is the second hardest material on earth. Corundum itself is not a very rare mineral, but fine crystalline forms of gemstone quality material are extremely rare. The corundum gemstone group includes two of the most valuable and popular gemstones on the market today - sapphire and ruby. The most common chrysoberyl that is highly transparent and typically yellowish-green to greenish-yellow in color.Ĭhrysoberyl that exhibits chatoyancy, a reflection of light reminiscent to the slit eye of a cat. Varieties of chrysoberyl gemstones include: Alexandrite:Ī rare color change variety of chrysoberyl that is red in incandescent light and green in daylight.Īn extremely rare variety of color change chrysoberyl (alexandrite) that also exhibits chatoyancy. The chrysoberyl group is perhaps most famous for its cat's eye gemstone variety, but the rarest and most valuable chrysoberyl is alexandrite - a highly desirable chromium-rich color change variety of chrysoberyl. It was formerly referred to as 'chrysolite', a historical name essentially describing any greenish-golden to olive colored gemstone. Yellow to golden to greenish golden beryl.Ĭhemical Composition: Beryllium aluminum oxideĬhrysoberyl was was first discovered in 1789 and since then, it has become one of the most important and valuable gemstone groups. Pink beryl colors can range from purplish-pink to peachy, or pinkish-orange to salmon. Light-green beryl that lacks chromium as a coloring agent.
Green beryl colored by chromium (sometimes vanadium). Light-blue to greenish-blue beryl that exhibits chatoyancy. Varieties of beryl gemstones include: Aquamarine: Although all beryl gemstones share a common chemical composition, they can vary significantly in transparency and clarity. The different varieties of gem-quality beryl are distinguished by their color and in some cases, their coloring agents. In its purest form, beryl is completely colorless. The beryl group is most famous for emerald, a rich green chromium colored variety of precious beryl.
The beryl family is considered to be one of the most important of gemstone groups.
Chemical Composition: Beryllium aluminum silicate
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