Many people associate its brilliant crimson colors with passion and love, making ruby an ideal choice for an engagement ring. Ruby is the red variety of the corundum mineral species, while all other colors of corundum are called sapphire.
This most sought after gemstone is available in a range of red hues, from purplish and bluish red to orangish red. Ruby is readily available in sizes up to 2 carats, but larger sizes can be obtained. However, in its finest quality, any size ruby can be scarce. In readily available small sizes, ruby makes an excellent accent gemstone because of its intense, pure red color.
Ruby is mined throughout Southeast Asia. While Thailand and Myanmar (Burma) produce exquisite examples of this gemstone that the ancient Sinhalese people called Ratnaraj, the King of Gemstones.
Despite all the best efforts of gemstone merchants to use technology to enrich color, fine ruby is still exceptionally rare. After being extracted from the earth, rubies today are commonly heated to high temperatures to maximize the purity and intensity of their red hue. Impurities may also dissolve or become less noticeable after heating. However, heating will only improve the color if the gemstone already contains the chemistry required. Occasionally rubies with small imperfections are permeated with a silicate byproduct of the heating process, which helps to make small fissures less visible. This enhancement, like heating, is permanent and rubies, whether enhanced or not, remain among the most durable of gems.