Sapphire | Cobalt Blue - The September Birthstone Sapphire is a deep, rich blue precious gem, a variety of the mineral corundum. It is the premier blue gemstone, the one against which all other blues are measured. Sapphire is the birthstone for September and the traditional gift to commemorate a 45th wedding anniversary. The name, sapphire, is derived from the Latin word “saphirus” and the Greek word “sapheiros,” both meaning "blue stone." The sapphire has been prized as an important … [Read more...]