Sapphire is a gemstone variety of the mineral corundum. Sapphire the celestial gemstone associated with the sky comes in almost every color of the rainbow with the most popular being blue. Blue sapphire has been associated with nobility, peace, truth, sincerity and faithfulness.
Sapphire has a hardness of 9 on the Mohs scale which makes it the hardest gemstone after diamonds (hardness 10).
The trace elements Iron and Titanium cause the blue color in sapphires. Differing amounts of the trace elements iron, titanium and Chromium cause most fancy sapphires colors. In the fancy sapphires pinks, yellows and greens are the most desirable colors.
The word "Sapphire" when used alone usually means the blue variety of the gemstone.
The main sources for Sapphire are Australia, Srilanka, Thailand and Madagascar. Other sources which have produced gem quality sapphires include Kashmir.
Thailand is the major trading/cutting center for sapphire exporting most of the production to the world.
Sapphire is the birthstone for the month of September.