he ruby is considered to be a precious stone, because it would not change its intense red color during heat treatment. The ruby is a strong stone, has a beautiful intense red color and is quite rare. There has been said that, because of the red color, the ruby stands for love, passion, courage and emotion. Also, the gemstone should protect against bad luck and give courage and authority. For centuries the ruby is considered to be one of the most valuable stones on earth. That’s why many rulers and kings wore and still wear rubies as jewellery and they decorate their clothes with rubies. It is also believed that the ruby has healing powers; it would injure infections, improve the immune system and purify blood.