Ruby is a #9 on Mohs scale, usually excellent in toughness, but with certain treatments or large fractures/inclusions can be less durable. Sources are Afghanistan, Kenya, Madagascar, Myanmar (Burma), Sri Lanka (Ceylon), Tanzania, Vietnam, and Thailand. Thailand is the world center for treatment and wholesale trade and mine production of rubies and has been declining since 1990s. Myanmar is considered to produce the finest quality of rubies. Where Sri Lankan rubies are often lighter in tone than rubies from Myanmar(Burma) or Thailand.
The name Burma or Burmese ruby is practically synonymous with the fine-quality ruby. Political changes let to the renaming of the country as Myanmar. But many people in the gem trade still refer as Burma ruby when they talk about the source of the world’s most prized rubies.
The first Burmese mines were located in Mogok, and the production fluctuated through much of the post-World War II era. The famous Mogok mining area of Burma(now the Union of Myanmar) has been so heavily mined for so many thousands of years that evidence is so rare. Yet the caves were once so rich that it’s unlikely that the early cave dwelling, tool-wielding humans who lived there were not aware of the dazzling red corundum crystals around them.
It was ruby in its reddest state that inspired the notion that rubies could cure blood disorders or heal wounds. People from distant past swallowed rubies whole or break them apart or pound them into powder and put them into liquid or pastry mixture, which they then rubbed on their skin. According to thirteenth-century medical from India, rubies were believed to cure digestive disorders.
Today, most rubies come from Myanmar and Madagascar. The discovery of a rich deposit in Mong Hsu helped the country get back to the forefront of ruby producers. Ruby is the US birthstone for July.