Ruby is gemstone that comes in different shades of the color Red. It is a variety of the mineral corundum. The trace element Chromium causes rubies to be red. For centuries Rubies have been associated with power, beauty, wisdom and desire. It is known to be the King of all gemstones, in the ancient language of Sanskrit ruby is called ratnaraj (King of Precious stones).

Ruby has a hardness of 9 on the Mohs scale which makes it the hardest gemstone after diamonds (10 on the Mohs scale).

There are many sources of Rubies but for centuries Rubies have been mined in Burma (Myanmar), Thailand, Cambodia, Srilanka, Vietnam and other sources include countries in Africa -Madagascar, Tanzania, Mozambique, and Kenya. Rubies deposits have also been found in India, Pakistan, Nepal and Tajikistan.

Thailand is the center of the corundum market/cutting center for Rubies exporting most of the world's faceted Rubies.

Ruby is the birthstone for the month of July.