It was mined in Minas Gerais, Brazil and cut in Idar-Oberstein, Germany. On display at the Smithsonian Institution, this 12,555-ct topaz has over a thousand facets. Two and three-phase inclusions have also been noted. Usually planes of two or more non-miscible liquids, each containing a gas bubble. In pegmatites and high temperature quartz veins also in cavities in granite and rhyolite in contact zones in alluvial deposits as pebbles. John's Island in the Red Sea where the gem was said to be mined. See "Identifying Characteristics" below.įrom the Sanskrit tapas for fire, alluding to the orange color, or from Topazios, an ancient Greek name for St. ![]() Green: colorless to blue-green/green to bright blue-green/colorless to bright green.Brown: yellow-brown/yellow-brown/weak yellow-brown.Dark rose-red: red to dark red/yellow to honey yellow/rose red.Pale blue: bright blue/pale rose/colorless.Dark yellow: citron yellow/honey yellow/straw yellow.As in ruby, this line may reverse and become fluorescent. Heat treated pink gems contain Cr and may show a Cr spectrum with a weak line at 6820. Heat Treatment, Irradiation, Surface Coating CVD treatment (surface coating) used to create mystic topaz. Most blue topaz has been irradiated and heat treated. ![]() ![]() This material fluoresces brownish yellow to orange in X-rays.įluorescent, UV-Long, UV-Short, X-ray Colors Sherry brown and pink: orange-yellow in LW, weaker in SW, sometimes greenish white in SW. See "Identifying Characteristics" below.īlue and colorless: weak yellow-green in LW, weaker in SW, greenish white to violet-blue in X-rays, and gems turn brown due to irradiation. There is a rough correlation between color and density, as follows: pink: 3.50-3.53 yellow: 3.51-3.54 colorless: 3.56-3.57 blue: 3.56-3.57. See "Identifying Characteristics" below. See "Identifying Characteristics" below.Ĭolorless, white, gray, pale to medium blue, greenish, yellow, yellow-brown, orange, pale pink, deep pink, tan, beige, red.
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