What causes black spots on white corundum?
Do you think white corundum should be white and flawless? In many cases, if you want to know the quality of white corundum, you can see it from the color, but sometimes we find that white corundum is mixed into it. What are these black particles?
Black impurities, such as impurities carried by itself or intentionally mixed, may cause black spots on white corundum; rust, white corundum raw materials contain iron oxide, which may be removed during the production process. Accidental mixing of rust due to mechanical rust can 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 low purity of white corundum itself, high impurity content, and small black spots may appear in the color.
Whether the color of white corundum is pure is one of the testing standards for the quality of white corundum, and the quality of white corundum does not meet the 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.