How Does A Sapphire Form - It is a stone of great hardness. Web sapphire (a corundum variety) is an aluminum oxide occurring in every color of the rainbow. Web aluminum oxide, as it is known in mineralogy circles, is formed by both volcanic processes deep in the earth and the high pressure and.
It is a stone of great hardness. Web aluminum oxide, as it is known in mineralogy circles, is formed by both volcanic processes deep in the earth and the high pressure and. Web sapphire (a corundum variety) is an aluminum oxide occurring in every color of the rainbow.