Rubies may be any shade of red, from pinkish to purplish or brownish red, depending on the chromium and iron content of the stone. Frequent twinning of the crystal makes the material liable to fracture, yet ruby is a tough mineral, second only to diamond in hardness.
Other varieties of gem-quality corundum are called sapphires. The ruby is considered one of the four precious stones, together with the sapphire, the emerald, and the diamond.
Chemical Formula: Al2O3:Cr
Hardness: 9
Ruby is an excellent stone for energy. It also encourages passion for life but never in a self-destructive way. Ruby improves motivation and setting of realistic goals. Ruby stimulates heart chakra and balances the heart.
