Sapphire Jewelry
Where the name comes from: Greek sappheiros "blue stone" though probably originally applied to lapis lazuli.Where the stones come from: Widespread, such as Madagascar, East Africa, Eastern Australia, Thailand, Sri Lanka and North America.
Chemistry: Aluminium oxide (corundum) with traces of impurities that give its colors, Al2O3 -
Colors: Mainly blue, though other colors are found, red colors of the same mineral are called rubies. Rubies and sapphires are often found in the same area.
...and another thing: Sapphires are the second hardest gemstones after diamond, they can only be scratched by a diamond. Sapphires are one of the four precious gemstones along with diamonds, emeralds and rubies.