Any color of corundum except red is called sapphire, although cornflower blue to bright blue is the most popular and sought-after sapphire gem color. Sapphire comes from the same places and in the same qualities as its sister stone, ruby, with the best color coming from Kashmir and Burma. The word "sapphire" alone refers to the blue variety. All other colors have the color name added to the stone, as in "orange sapphire" or "pink sapphire." Sapphire often has some inclusions, but clarity is still quite good. Yellow, pink, orange, purple, and other colors are available in gem qualities.
Sapphire is said to be a mind-opening gem. It is supposed to relax the wearer and clarify thought, as well as attract "divine favor." Sapphire is said to prevent envy and fraud, and bring truth and good health. It was believed to be a powerful antidote for poison.
A Star Sapphire is an opaque variety of this gemstone that displays a six-rayed star, called an asterism, under certain light. Star sapphires come in many colors as well.
Sapphire is the birthstone of September. Sapphire includes all colored varieties of corundum, with the color coming from iron and titanium. It is the second-hardest mineral in existence (at 9 on the Mohs scale) and so it wears very well. Often, sapphires used in jewelry are heat-treated or given chemical diffusion to enhance their color; these enhancements are permanent.