The remarkable characteristics of the 6 carat ruby stone make it stand out in addition to its size. One form of the mineral corundum that is well-known for its deep red hue stemming from chromium content is the ruby. A 6 carat ruby stone has an intensely red color that is rich and deep; in the gemstone trade, this color is referred to as "pigeon's blood" and is the highest grade. A 6 carat ruby's clarity and transparency are major factors in determining its value; the less inclusions in the stone, the more desirable it is.