Topaz/ Beryl- Key Terms

Topaz

• Red and pink topaz varieties, including imperial topaz, are the most rare and valuable.
• Color centers and traces of chromium cause the wide variety of colors in topaz.
• Topaz crystals are often cut as long ovals, pears, or emerald cuts due to their elongated shape.
• Topaz requires special care in cutting, polishing, mounting, and wear due to its cleavage.

Treatment of Topaz

• Virtually all topaz is treated to produce a blue color.
• Treatment involves heating or a combination of heating and irradiation.

Aquamarine

• The finest aquamarines are a moderately strong, medium-dark blue to slightly greenish blue.
• Brazil, Pakistan, and China are leading producers of aquamarine.
• Virtually all aquamarine is heat-treated to remove the yellow color component and produce a more marketable blue color.

Imperial Topaz

• The definitions of imperial topaz can vary widely.
• The Ouro Preto area of Brazil is the world’s major commercial source of imperial and red topaz.

Other Beryls

• Morganite is almost always heated, or irradiated first and then heated, to produce or improve the pink color.
• Traces of manganese cause red beryl’s color.
• The US state of Utah is the world’s only known source of red beryl.
• Tone and saturation levels distinguish green beryl from emerald.

Key Terms

• Imperial topaz: A widely used trade term for gem-quality topaz of medium reddish orange to orange-red color.
• Precious topaz: A trade term for orange-to-yellow and brown topaz.