1. Watching: During the formation process of natural crystal, it is always affected by the environment and always contains some impurities. When observing the sun, you can see faint uniform and small horizontal stripes or catkin-like substances. The fake crystals are mostly smelted with inferior crystal slag and glass slag, which are polished, colored and imitated, without uniform stripes or catkins.
2. Tongue licking: Even in the hot summer days, licking the natural crystal surface with your tongue will feel cold and cool. Fake crystals don't feel cool.
3. Illumination: The natural crystal is placed vertically under the sunlight, no matter from which angle it is viewed, it can emit beautiful brilliance. Fake crystals cannot.
4. Hardness: Natural crystals have high hardness. Gently scratch the jewelry with crushed stones without leaving traces; if there are streaks, it is fake crystal.
5. Check with a polarizing lens: the one that has four bright and four dark changes when rotated 360 degrees under the polarized lens is natural crystal, and the one that does not change is fake crystal.
6. Check with two colors: natural amethyst has dichroism, while fake crystal has no dichroism.
7. Check with a magnifying glass: Check with a ten times magnifying glass under transmitted light, and the bubbles that can be found can basically be regarded as fake crystals.
8. Check with hair strands: Put the crystal on a strand of hair, and the double shadow of the strand of hair can be seen by the human eye through the crystal, it is natural crystal, mainly because the crystal has birefringence.
9. Test with thermal conductivity meter: Adjust the thermal conductivity meter to 4 green grids to test gemstones. Natural crystals can rise to 2 grids of yellow, while fake crystals do not rise. When the area is large, it will rise to 1 grid.