[Fr., from L. rubeus, red.] A precious stone of a blood-red color, ranking in hardness next to the diamond. It is a red crystallized variety of corundum. The finest are Oriental rubies brought from Burmah, and are more valuable than diamonds of the same size. They occur in crystalline limestone, and consist of pure alumina, with the color of pigeons' blood. The spinal ruby consists of alumina and magnesia, and is found in Ceylon and Siam, varying from deep red to rose red in color.