Rubies are considered one of the “Big 3” precious gems and often command the highest prices per carat amongst all colored gems. Over 95% of rubies are heated to improve their color. Natural, unheated rubies are more rare, and more valuable, than heated rubies of the same quality.
Ruby is a 9 out of 10 on the Mohs Scale of Hardness, second only to diamond. Their resistance to scratching, in addition to their beauty, is another reason why they’re so popular in jewelry. Although historically the most valuable rubies have been mined in Burma (Myanmar), many other locations have produced very fine quality, beautiful, and valuable rubies. Several of these locations include Thailand, Cambodia, the Himalayas & northern Vietnam.