Ruby is the most valuable variety of the corundum mineral species, which also includes sapphire. It’s one of the most popular traditional jewelry stones and is exceptionally durable. Its colours,  always red, can reach vivid levels of saturation. Historically, rubies have been mined in Thailand, in the Pailin and Samlout District of Cambodia, as well as in Afghanistan, Australia, Brazil, Colombia, India, Namibia, Japan, and Scotland; after the Second World War ruby deposits were found in Madagascar, Nepal, Pakistan, Tajikistan, Tanzania, and Vietnam. Ruby is the birthstone for July.