Ruby, Al2O3, is the red variety of corundum. All other colors of corundum are known as sapphire. Ruby is one of the most valuable of gemstones and is the birthstone for July. It is found all over the world but most notably in Thailand, India, Kenya and Burma.
Ruby is extremely hard, being 9 on the mohs scale. It has a refractive index of 1.76 to 1.78 and a trigonal crystal system. To view our finished ruby jewelry, click here. We have the following ruby gemstones in stock: