However, the 4Cs for stars are different.Ĭolor – Asterated corundum qualifies as a star ruby as long as it is properly polished with a star, and has any amount of red in it. Like most gemstones, star rubies also follow the usual 4Cs of color, clarity, cut, and carat weight. Not all rubies display silk like this, or at all, though it is very common. The most well-known source of star rubies is Myanmar (formerly known as Burma) due to how the silk forms in a very organized, and tightly knit fashion.

It is possible for them to show other phenomena, but this happens only rarely. Rubies mainly show asterism, and rarely chatoyancy. These effects include asterism, chatoyancy, iridescence, adularescence, aventurescence, labradorescence, and play-of-color. Special features that appear in gems like a star are known as phenomena. Each star ruby is so unique in appearance, that matching pairs (much less a set) is nearly impossible. Even more so in comparison to star sapphires, since the chromium that colors them pink and red limits the sizes they can grow to.

Star rubies are amongst the rarest and most coveted gems in the world.

Black star sapphire price per carat