How rare are star rubies?
Today, out of every 100 rough corundum (ruby and sapphire) mined; only three will have stars apparent after being cut into cabochons. Out of these three, one will have a poor color but a good star; one will have a poor star but a good color and only one out of hundred will have both a good star and a good color! Most original sources of star rubies such as Mogok (Burma) have run out of supplies. Worldwide production today is yielding a very small quantity of fine stars (especially in sizes above 5 carats). Star rubies are becoming rare as most rough today is cut into faceted stones after heating instead of being cut into cabochons to display the star.
