About the "burn" of gemstones, what is meant by "no burn"?

The "no burn" of gemstones refers to the state of being purely natural and not having undergone any processing or beautification.

Gemstones are generally burned, ninety percent of the gems on the market are burned, is the traditional way to optimize the gemstone. This is called having a burnish.

The best way to determine whether a gemstone is burned or unburned is to rely on a gemstone certificate. Some of the world's leading laboratories, GUBELIN and GRS in Switzerland, AGL in the United States, Central TGL in Japan, GIC and CGL in Lanka, all indicate in their certificates whether or not they have been heat-treated.

Expanded Information:

The purpose of "burning" a gemstone is:

1. To make it more appealing to the eye

Although imperfections cannot be avoided during the formation of a gemstone, buyers will always want to buy a gemstone that is bright in color, the interior of the stone is pure and clear.

The most common way to optimize gemstones for the market is to burnish them.

2. Burning only changes the appearance

Heating a gemstone to optimize it can only achieve two results: one is to change the color of the gemstone, and the other is to change the appearance of the inclusions inside the gemstone.

This is in fact the same process that a gemstone undergoes in nature, only at a different time, and the color of the heated gemstone becomes more intense, more dazzling and more fascinating.

Reference: Baidu Encyclopedia - Gemstones