Ruby is distinguished for its bright red colour, being the most famed and fabled red gemstone. Beside for its bright colour, it is a most desirable gem due to its luster, durability, hardness and rarity. Large sized transparent rubies are even rarer than Diamonds. In essence, Ruby is a red Sapphire, since Ruby and Sapphire are identical in all properties except for colour. However, because of the special allure and historical significance, Ruby has always been classified as an individual gemstone.