Sapphire

Sapphire is gem-quality corundum, which is aluminium oxide in crystal form. Pure corundum has no colour; small amounts of other elements tint it, so that besides the familiar blue it is found yellow, green, purple, pink, orange, grey, black and colourless, and the trade calls every colour but blue a 'fancy' sapphire. Pink sapphire grades into ruby with no fixed chemical boundary, and laboratories separate the two by the colour they see. At 9 on the Mohs scale it resists scratching, which is why grown sapphire is made into watch glasses and other hard windows. Natural stones are often heated to change their colour and clarity. The word reaches English through French and Latin from Greek, and the ancient word may once have meant lapis lazuli or another blue stone. It is the customary birthstone for September. Cunningham links sapphire with the Moon, water and Apollo, saying the Greeks wore it to consult the oracle at Delphi. He uses it to widen psychic awareness, in meditation and for wisdom, as a guardian of love and fidelity, for peace, in protective and defensive magic, in legal matters, in healing work and in rites for money and wealth. Hall calls it the wisdom stone, one that steadies the mind and brings prosperity.