A very common treatment used on many gems you find on the market today is heat. The process of treating a gem with heat can yield a richer coloring or improve the clarity of the stone.

You may not know that most citrine is made by heating amethyst. We end up with that rich yellow/orange coloring citrine is valued for. And as mentioned in the previous post, sapphires and rubies are often treated to improve the stone’s color and clarity.

Much of the aquamarine on today’s market is heat treated to remove natural yellow tones, and to change the original green color into the more desirable blue or “aqua” the gem is named for. Heat treatments on aquamarines can also be used to enhance its existing blue color to deeper and richer blue. Likewise, almost every bit of tanzanite available for purchase has been heated at low temperatures to eradicate brown undertones and give a more desirable blue/purple color.

Heat treatments are widely accepted and very widely used to improve gemstones.