Formula: | Al2(SiO4)(FOH)2 | Click to see a larger image |
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Crystal: | Orthorhombic | |||
Hardness: | 8 | |||
Spec. Gr.: | 3.49-3.57 | |||
Streak: | White | |||
Cleavage: | Basal cleavage | |||
Location: | Miami, Zimbabwe |
Fine naturally colored blue topaz crystals have been formed at the Xanda, and Lomoeiro mines near Virgem da Lapa, Minas Gerais, Brazil; Alabaschka, Ural Mts., Russia; Little Three Mine, Ramona, California; and at Miami, Zimbabwe. Crystals from Miami are seldom faceting grade, but are well-formed singles from two centimeters on an edge to six centimeters. Some contain gemmy green tourmaline crystals as inclusions. The mine has been shut down in recent years. Many almost flawless white topaz from the rivers of Brazil are now being irradiated into beautiful and relatively inexpensive faceting grade blue topaz. Ancients believed that topaz conferred cheerfulness upon its wearer, calmed the passions and prevented bad dreams. An old verse honors this birthstone: "Firm friendship is November's, and she bears true love beneath the topaz that she wears." |
Bibliography: Bancroft, Peter, Gem and Crystal Treasures, 1984, pg. 313-316. |
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