Why does white corundum have black spots?
Do you think that white corundum should be white and flawless? In many cases, if you want to know the quality of white corundum, you can tell by its color, but sometimes we will find that white corundum will be mixed with it. What are these black particles?
Black impurities, such as impurities carried by themselves or impurities that are deliberately mixed, may cause black spots on white corundum; rust, white corundum raw materials contain iron oxide, which may be removed in the process of production. Accidental incorporation of rust due to mechanical rust will also lead to impure color of white corundum.
If the smelting time is not enough, it can also be considered that the smelting process is immature, resulting in the low purity of the white corundum itself, the high impurity content, and the possibility of small black spots in the color.
Whether the color of white corundum is pure or not is one of the testing standards for the quality of white corundum, and the quality of white corundum is not up to standard, which also has a great impact on the performance of white corundum, such as hardness and grinding force. In this regard, manufacturers are required to have strict requirements on themselves.