Where is the quality of white corundum/white fused alumina/white aluminum oxide /WFA/WA/White aloxide?

Where is the quality of white corundum/white fused alumina/white aluminum oxide /WFA/WA/White aloxide?
The main production areas of white corundum/white fused alumina/white aluminum oxide /WFA/WA/White aloxide are: Henan and Shandong
The reasons for the quality difference between Henan white corundum/white fused alumina/white aluminum oxide /WFA/WA/White aloxide and Shandong white corundum are as follows:
1. Raw material: alumina powder, the alumina powder used in Henan White Corundum Factory has better quality and higher price
2. Smelting time: Henan white corundum/white fused alumina/white aluminum oxide /WFA/WA/White aloxide  has a longer smelting time, and the bulk density and hardness of white fused alumina are high