Ruby belongs to the Corundum crystal family, along with Sapphire. It is very tough and very durable, and can range in colour from a pinkish red to a blood red. Ruby is mined in quite a few different places; presently Mozambique is the biggest production centre, but the source there was only discovered in the early 2000s.
For many centuries the fabled Mogok valley of northern Burma ( Myanmar ) was the main world source for this gemstone. Nowadays the Mogok no longer produces the extremely high-end, super-expensive big blood-red crystals it once did, but it is still a good source for fine quality AGrade commercial Ruby, as in the earstuds above, and the cachet in the term “Burmese Ruby” is still genuine.