Cubic Zirconia Rings
One of the best gemstones that have been synthetically produced by humans, a Cubic Zirconia is composed of Zirconium Dioxide. This gemstone can be taken as the finest example of human creation as it acts as a low-cost substitute for a Diamond which makes it much more important. Though it can be produced in several colors, but usually is made colorless to bear the looks of a diamond in itself.