Zircon resembles diamond in its luster and fire, yet it has a tendency to chip out at the facet junctions over the years, so it not prized as highly. (Cubic zirconia, a well-known diamond simulant, is an altered form of the mineral baddeleyite, whose chemical composition is zirconium oxide.)

Class: semiprecious
Origin of Name: from the word zargoon, meaning vermilion in Arabic or golden-colored in Persian
Color: vermilion, yellow, green, brown, blue, clear
Chemical Composition: zirconium silicate
Crystal System: tetragonal
Hardness: 7.5
Specific Gravity: 4.6-4.7
Geographic Origins: Burma, Sri Lanka, Cambodia, Vietnam

Photo: ©International Colored Gemstone Association

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