THE ULTIMATE GUIDE TO DIAMOND

The most common kind of crystalline alumina, α-aluminium oxide, is called corundum. When trace factors make it show up pink it is recognized as ruby, but all other colorations slide beneath the designation sapphire. Corundum provides a trigonal Bravais lattice with a space group of R-3c (variety 167 in the Global Tables).Cerium Oxide is the princi