This is a natural sapphire that has been mined in Australia. This gem has not been heated or treated in anyway.
The sapphire is one of the two or three gem-varieties of corundum, with another one being the red or deep pink ruby. Although blue is their most well-known color, sapphires are made up of any color of corundum except for red. Sapphires may also be colorless, and they are also found in shades of gray and black.