Ruby = Red Sapphire
Did you know that a ruby is simply a red sapphire? Sapphires are found in every color of the rainbow. Every sapphire is made of the same substance – aluminum oxide. Pure aluminum oxide is transparent. Trace elements within the sapphire cause the various colors. Small amounts of chromium result in a ruby. Blue sapphires contain iron and titanium. The reason rubies are much rarer than blue sapphires is because there is far less chromium in the earth than iron and titanium.