| Hazard Information | Back Directory | [Description]
Sapphire occurs in a wide range of colors such as blue, pink, padparadscha
orange, yellow, green, purple, black. Color is due to trace impurities of Fe2+, Fe3+, Ti, and
yellow color centers. The most expensive color is an intense cornflower blue; these are sometimes referred to as "Kashmir" sapphires having a highly saturated, slightly milky, violet
blue color. Padparadscha is next in value, followed by pink, then orange, purple and yellow,
respectively. Nowadays 400–500 tonnes of synthetic sapphire are produced by the Verneuil
process each year.
| [Occurrence]
Sapphire is exclusively mined from gem gravels or clay
resulting of the weathering of basalt. Major deposits are similar to those for mining ruby,
that is, Myanmar, Thailand, Sri Lanka, Australia and East Africa (i.e., Tanzania, Kenya, Nigeria, with lesser amounts from Malawi and Burimundi). Historically, sapphire have been
mined from pegmatite veins in marble in the Jamu-Kashmir region (India) since 1881. | [Uses]
In jewelry, as phonograph needles, industrial abrasive, watch and instrument bearings. |
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