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| Formula: | Ca5(PO4)3 (FClOH) |  Click to see a larger image |
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| Crystal: | Hexagonal | |||
| Hardness: | 5 | |||
| Spec. Gr.: | 3.1-3.2 | |||
| Streak: | White | |||
| Cleavage: | Imperfect basal | |||
| Location: | Llallagua, Bolivia |
| Apatite typically forms in six-sided prismatic crystals. It occurs in shades of green, blue-green, or brown, also colorless, yellow, violet, red, and deep blue. It is too soft for a gemstone. Since it has so many variables of form and color, it has long been mistaken for beryl, quartz, nepheline, and tourmaline. However, near the end of the 18th century, A. G. Werner of the Bergakademie in Freiberg, Germany discovered that it was a new mineral. He named it Apatite after the Greek APATAO, meaning, "I am misleading." Apatite crystals may be many faced, short or long, columnar to acicular, and are found embedded, attached or loose. Extraordinary, prismatic, water-clear, violet, terminated crystals up to 3.5 cm were found at Val Casatscha, south of Mompe'-Medel, Switzerland. Other noteworthy occurrences are: Mt. Apatite, Auburn, Maine; pink crystals from the Haramosh Valley, Pakistan; and at Llallagua, Bolivia. |
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Bibliography: Weibel, Max, Die Mineralien der Schweiz, 1966, pg. 52 and 139. Bancroft, Peter, Gem and Crystal Treasures, 1984, pg. 171-175. |
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