Zircon – Natural, Faceted, Blue
Notice how the top facets appear crisp but the back facets look blurred. This is due to high birefringence in zircon, but the effect is more subtle in other diamond imitations. Blue zircon ring designed by Jason Baskin. Photo by The Gem Vault. Licensed under CC By 2.0.
Credit: The Gem Vault
|Natural or man made