The hardness of topaz is seven. Topaz is called crystal topaz in the gem world. Its color ranges from light yellow, regular yellow, orange yellow, olive yellow to golden yellow.
Due to its excellent brightness and color saturation, any transparent and smooth surface is considered top-quality, and it is far more transparent than yellow jade, making it highly favored by consumers and often cut into pendants or ring faces. Due to the rarity of natural citrine and its relatively high price.
Appreciation and Collection
Pure natural citrine 1. Fracture identification. The pattern of glass fracture is familiar to everyone, which is a smooth and curved indentation like a shell; And crystal is a mineral, with a stone like texture visible at the fracture surface. Moreover, crystal is a crystalline body, and there will be no traces like glass on the fracture surface. 2. Thermal conductivity testing, adjust the thermal conductivity meter to 4 green grids to test the gemstone. Natural crystals can rise to 2 yellow grids, and when the area is large, it rises to 1 yellow grid, while fake crystals do not rise. 3. By hand feel, crystals are all crystals with fast heat transfer, while glass is amorphous with slow heat transfer. So holding the crystal will make you feel icy cold in your heart, and after wearing it for a while, it will synchronize with your body temperature; Glass, on the other hand, has a temperature sensitivity. 4. Measuring hardness: The hardness of natural crystals is 7, while glass is only 5. Therefore, during testing, any object with a hardness greater than 5 can scratch the glass. 5. Judging by the price, you get what you pay for. Even natural crystals come in multiple grades, resulting in a huge difference in price. There are not many high-quality natural yellow crystals, so don’t expect to buy 3A grade yellow crystals at a low price. The better the crystal, the more expensive it is. 6. Hair identification (birefringence), hair identification specifically targets spherical crystals: place the crystal on a hair strand, gently rotate the crystal, and when it rotates in a certain direction, a double shadow appears, that is, one hair turns into two, the effect is clear and obvious. This is a birefringence phenomenon caused by the crystal arrangement of natural crystals, which cannot be achieved by fake crystals. The more obvious the double shadow effect, the better the crystal quality. Some natural crystals with excessive impurities may not have obvious double folding, or may have twisted hair, straight lines, broken lines, and other phenomena, resulting in poorer crystal quality. 7. Optical identification shows that glass is a homogeneous body that does not crystallize, while crystal is a heterogeneous body that crystallizes. When rotated 360 degrees under a polarizing mirror, natural crystal changes between light and dark, while fake crystal remains unchanged. In addition, some natural crystals such as amethyst have dichroism, while fake crystals do not. 8. Upon observation of the contents, most synthetic crystals have a pure and large interior, appearing perfectly flawless; Natural crystals generally have some “flaws” such as “cotton” and cracks to varying degrees. There are many natural products that are very pure, but they are very rare. rarity is considered precious, which is reflected in their price. For yellow crystals with the same block size and color clarity, natural products are far superior to synthetic crystals.
