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Sapphire:
Simple Oxides (Aluminum oxide) Al3O3 AKA: Corundum |
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System: Hexagonal; sometimes tapering prismatic; also pyramidal, tabular; often striated. Appearance: Pink, blue, green, violet gray, yellow or other colors; vitreous, adamantine; streak white. Physical Properties: Hardness: (9.0); Specific gravity: (3.9 - 4.1). Cleavage: None; often conspicuous parting in three directions. Fracture, uneven, conchoidal; transparent to translucent; fluorescent; brittle. Similar species: Feldspars. The fine striations on parting faces might lead to confusion with the plagioclase feldspars, but corundum may be recognized by its superior hardness and high gravity. Occurrence: Corundum forms in several distinctive environments. It occurs associated with albite and acmite in nepheline syenite pegmatites; with andalusite and cordierite in hornfels of contact metamorphic rocks; and with muscovite, almandine and oligoclase in gneiss and hornfels of metamorphic terrains. Gem quality sapphire has only been found in a few places in North America, primarily Montana. Large deposits of emery have been found in New York. Miscellaneous: Blood-red corundum is called ruby and is the rarest and most valuable gemstone. All other gem-quality corundum is called sapphire, and may be pink, blue, green, violet gray, yellow or other colors. May be clear or contain bundles of tubelike inclusions, giving "star" or "cats eye" effect in cut or polished stones. Some sapphire is faceted, but most are fashioned into cabochons. Sapphire is the birthstone for September. Corundum is used as an abrasive. Conventional Wisdom: Sapphire can be used to rid one of unwanted thoughts and to bring joy and peace of mind via opening the mind to beauty and intuition. The sapphire is known as the stone of prosperity, sustaining the gifts of life, eliminating frustration, and fulfilling the dreams and the desires of the consciousness. It tends to focus, to emanate, and to radiate energy without ones conscious initiation. Black sapphire: Provides a grounding force, protection and centering. Green sapphire: Stimulates loyalty and encourages the remembering of dreams. Star sapphire: Enhamces the centering of ones thoughts. It helps make one cheerful and friendly. White sapphire: Provides for focus and directing of attention. Yellow sapphire: Brings endurance, fullfilment of ambition, and the emanation of a pleasant rapport to the user. Belongs to the Astrological Signs of Virgo, Libra and Sagittarius. |