Established in 1939, The Natural Sapphire Company is a leader in the sapphire retail industry. Their website, http://www.TheNaturalSapphireCompany.com is known worldwide for having the largest collection of natural sapphires, using the latest design techniques, and providing the best information about sapphires. Their stones are unaltered in any way. They are not irradiated, diffused, glass filled, oiled, or synthetic, and very few are heat treated.