What's the difference between an unburned gem and a burnt gem?

Combustion is divided into optimization and treatment. Optimization is simply physical heating. After heating, the color of sapphire will become better, and the properties of sapphire will not change, so it is accepted by the industry and consumers. The treatment is also heating, but other substances are added during the heating process, and additives remain in the gem after heating, such as sapphire filled with high lead glass, which has greatly changed the sapphire and is not recognized and accepted.

Although it is difficult to find a ruby that does not burn, it is recommended to treat it at high temperature without chemical treatment, because this is the real gem worthy of long-term collection. In addition, it depends on the weight, color, clarity, cutting and final proportion. As for how to distinguish between burning and not burning, the best way for ordinary people is to rely on the gem certificate. Some world-renowned laboratories, such as Gubyrin and GRS in Switzerland, AGL in the United States, TGL in Japan, GIC and CGL in Sri Lanka, will indicate on their certificates whether they have been heat-treated.

How to judge whether there is a fever?

1, look at the color

After optimization, the color and tone of the gem are changed, such as burning the original light yellow or pink into dark yellow, dark brown, yellow and golden yellow; Some gray rough stones, milky white and silky in texture, were burned into blue; Deep blue and light blue can also be burned into pure blue.

Step 2 look at physical characteristics

After high-temperature heat treatment, a series of changes may occur in the inclusions of gemstones, such as needle-like inclusions becoming discontinuous, gas-liquid inclusions bursting, low-melting-point inclusions rounding, and filiform rutile needles disappearing.