Red varieties of corundum are known as rubies, while all the other colors are called sapphires. Their red hue, ranging from light pinkish red to purple red, comes from traces of chromium.
Sapphires are a form of gemstone-quality corundum, which is aluminum oxide that has crystalized as a result of pressure and heat deep underneath the Earth’s surface. Inclusions of small amounts of other elements, such as iron and chrome, can color the sapphire.
Emeralds have been valued since ancient times for their rich green color, and history records show them prized around the world, from Egyptian pharaohs to the Incas and Aztecs of South America.
The name “tourmaline” is from the Singhalese (language spoken in Sri Lanka) “tura mali”, which roughly means “stone with mixed colors.” There couldn’t be a more appropriate name for this semi-precious stone, which comes in an endless variety of colors.