Sapphire

Precious gemstone:

• The true sapphire is deep blue, yellow corundum is called yellow sapphire or Oriental topaz.
• Pale pink stones are called pink sapphire.
• Excellent sapphires occur in alluvial deposits of sand and gravel in Sri Lanka.
• Other important sources of the stones are Thailand, India, Afghanistan, China, the Ural Mountains and elsewhere in the former Soviet Union, and Queensland, Australia.
• In the United States sapphires are found in North Carolina, and near Helena, Montana.
• Sapphires and rubies are used as hard bearings in watches and scientific apparatus.