6mm Blue Sapphire Pendant in 14 Karat GoldThe word sapphire comes from the Greek translation for blue and was used in ancient times to describe any blue stone, often lapis lazuli. Around 1800 it was discovered that sapphires are a gem variety of corundum, the other being ruby. Corundum is a hard stone, rating a 9 on the Mohs scale, making it the second hardest natural mineral. Its chemical composition is aluminum oxide. The many colors in which corundum occurs are due to the presence of other