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Zoisite:
Sorosilicates (Basic calcium aluminum silicate, often with some iron and manganese; epidote group) Ca2Al3Si3O12(OH) AKA: Tanzanite, Thulite |
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System: Orthorhombic; usually in long prismatic crystals deeply striated along length; also columnar, bladed, fibrous, compact. Appearance: Gray, yellowish brown, greenish, pink (thulite), blue (tanzanite); vitreous, pearly on cleavage; streak white. Physical Properties: Hardness: (6.0 - 6.5); Specific gravity: (3.2 - 3.4). Cleavage: good, one direction, lengthwise; fracture, uneven to conchoidal; transparent to translucent. Similar species: Tourmaline has no cleavage. Pink tourmaline may be mistaken for thulite, but it does not fluoresce. Occurrence: Zoisite is not a common mineral and is restricted to metamorphic rocks. It occurs with chondrodite, tremolite and wollastonite in hornfels of contact metamorphic rocks, and with hornblende, almandine and glaucophane in blue schist of regional metamorphic rocks. Thulite has been found in Norway, North Carolina and California. The blue gem-quality variety, tanzanite, has only been found in Tanzania, East Africa. Miscellaneous: Zoisite was named after Baron S. Zois van Edelstein (1747 - 1819), and thulite after Thule, an ancient name for Norway. Conventional Wisdom: This mineral can provide for decomposition of negativity and for transmutation of the negative energies to positive force-fields. It can be used to dispel laziness and idleness. Belongs to the Astrological Sign of Gemini. |