gemstone

Diamond (or Cubic Zirconia)

Carbon (C) or Zirconium Dioxide (ZrO2)

AI-generated identification · may be incorrect

Hardness: 10 (Diamond) or 8-8.5 (CZ); Color: Colorless; Luster: Adamantine; Crystal Structure: Isometric; Cleavage: Perfect octahedral (Diamond) or none (CZ); Specific Gravity: 3.52 (Diamond) or 5.6-6.0 (CZ)

Hardness: 10 (Diamond) or 8-8
Color: Colorless
Luster: Adamantine

Identified July 6, 2026More gemstone →

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Physical properties

Formation & geological history

Natural diamonds form under high pressure and temperature in the Earth's mantle; Cubic Zirconia is a lab-grown synthetic mineral. Most natural diamonds are 1 to 3.5 billion years old.

Uses & applications

Used in fine jewelry (rings, earrings), industrial cutting/grinding tools, and high-tech optics.

Geological facts

Cubic Zirconia is the most common diamond look-alike and was first synthesized in 1970. Diamond is the hardest known natural substance on Earth.

Field identification & locations

Identify using a diamond tester or by checking for high dispersion (fire). Look for sharp facet edges and high refractive index. Natural diamonds are found in kimberlite pipes.