The most important gems from a commercial point of view, after the diamond, are the ruby and the sapphire, which despite their different appearance, both belong to the same mineralogical family, the corundum.
Corundum with yellow, orange, violet, colorless and green colors are also found in nature. Corundum, if it were pure, would be totally colorless; in fact the hues of ruby and sapphire are due to traces of metal oxides.
Corundum is a remarkably hard stone, second only to diamond. The name “ruby” comes from the Latin “rubeus”, meaning red. The color of the ruby actually varies from a pale pink, through all shades of red, to a dark crimson. The color of the ruby is due to traces of chromium.
The meaning that was given to these stones in ancient times is interesting: owning rubies meant dominion, love and faith.