A ruby is a pink to Pigeon blood red colored gemstone, a variety of the mineral corundum (aluminium oxide). The quality of a ruby is determined by its color, cut, and clarity, which, along with carat weight, affect its value. The brightest and most valuable shade of red called blood-red or pigeon blood, commands a large premium over other rubies of similar quality. After color follows clarity: similar to diamonds, a clear stone will command a premium, but a ruby without any needle-like rutile inclusions may indicate that the stone has been treated. Ruby is the traditional birthstone for July. The most famous and very high valued Ruby are from Mogok, Myanmar.