Cubic Zirconia is the most widely used and most affordable diamond imitation. It is a completely synthetic stone, not found in nature. It is often called cubic zircon.
Of course, zirconium is naturally occurring in nature, but it is not cubic but square sosutava and chemically different from cubic zirconia.
Clear version
Beautiful shimmering facet cut, ideal wherever you need a little shine for a few crowns :-) of suitable material