Sapphire: Sapphire is a gem variety of the mineralcorundum. When corundum is reddish blue to violet-blue, it is known simply as “sapphire.” Corundums of any other color (except red, which is ruby) are known as “fancy sapphire.”

On the basis of dollars spent in the United States, sapphire is the most popular blue stone and the third most popular colored stone (after emerald and ruby). Sapphire has a Mohs hardness of 9 and can be used in almost any type of jewelry without fear of being scratched.

Sapphire was traditionally mined in Southeast Asia, India, and the island nation of Sri Lanka. Recent discoveries of sapphire in several parts of Africa are bringing beautiful stones to the market from brand-new sources.