Rubies, along withdiamonds, sapphires, andemeralds, are the only types of gemstone characterized as precious.
Rubies are perhaps best known for being the July birthstone.
Once they return to normal, they emit a red light.
The Untold Truth Of Rubies
Rubies, along with diamonds, sapphires, and emeralds, are the only types of gemstone characterized as precious. Rubies are also one of the hardest natural substances in existence — at 9 on the Mohs Scale of Hardness, only diamonds are harder, with sapphires and rubies being evenly matched.
