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Celebrating ‘Ratnaraj,’ the Birthstone of July

All hail ruby, the birthstone of July, and one of the most widely celebrated colored gemstones. Technically the mineral corundum, all rubies are red. In any other color corundum is not classified as ruby, it is called sapphire.



Ruby is the second hardest gemstone after diamond, with a Mohs rating of 9. That hardness has made it a historic favorite for adornment among priests, warriors, and nobles. In ancient Sanskrit, ruby is called ratnaraj, which means “king of gems.” To this day ruby is considered “the gemstone of nobles.” The late Queen Elizabeth II wore the Burmese Ruby Tiara, one of the crown jewels, on many occasions during her reign.

Queen Elizabeth II Ruby Tiara

The world’s finest Rubies have historically come from Southeast Asia and more recently, from eastern Africa. The people of Myanmar (Burma) believe that rubies protect people from evil. High chromium saturation is what causes it to appear red. In addition to being the birthstone of July, ruby is also the traditional gift on wedding anniversary #40 –  though you don’t have to wait that long (hint, hint).

Ruby ring
$30 million Sunrise Ruby | Credit: Christie’s

In the market?

Rubies are often subjected to heat treatment, to produce a more pronounced red color. This process can also remove tiny needle-like inclusions called “silk,” improving the color tone even further. Such treatments are accepted when disclosed, as they are stable during normal wear. Unstable treatments like dyeing and fracture-filling – where breaks and cavities that extend to the surface are filled with glass – are less accepted since exposure to heat or chemicals can cause damage. It’s important, when buying or selling, to clearly disclose any treatments that have been applied.

Estrela de Fura ruby
$34M Estrela de Fura | Credit: Sothebys


Read about the Estrela de Fura and it’s sale

Read about the Sunrise Ruby, and six more!

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