Sapphire comes in many different colors, including green, pink, yellow, purple, orange and white. Most natural green sapphire is dark, olive-green in color and quite inexpensive although a few are bright and lively enough that they command premium prices. Traditionally, green sapphire has been produced in Thailand and Australia, but recent production has included many gems from East Africa.
Pink Sapphires have traditionally been found in the gem gravels of Sri Lanka, but recently a major find of intense color stones has been discovered on the island of Madagascar. Colors range from light pink to fuchsia. If the color intensity approaches red, the gem is a ruby, or if the pink color is mixed with orange, the term "padparadsha" is used.
Almost all sapphires of any color have been heat treated to lighten or intensify color, or to try and improve clarity. Since 2001 most pink, yellow and orange sapphire has been diffused with Beryllium to improve color. This treatment is impossible to detect without very specialized lab equipment. Recently, fracture filled stones have also appeared in the market.
Sapphire with a hardness of 9 is among the most durable of gemstones with only diamond being harder to scratch.
Treatments: Heat for color and clarity, diffusion for color, fracture filling for clarity enhancement.