mineral

Diamond (or Cubic Zirconia)

Crystallized Carbon (C) for Diamond; Zirconium Dioxide (ZrO2) for CZ

Hardness: 10 (Diamond) or 8-8.5 (CZ); Color: Colorless to faint yellow; Luster: Adamantine; Crystal structure: Cubic; Cleavage: Octahedral for diamond; Specific Gravity: 3.52 (Diamond) or 5.6-6.0 (CZ)

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

Identified May 3, 2026More mineral →

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Physical properties

Formation & geological history

Natural diamonds form under high pressure and temperature in the Earth's mantle over billions of years. CZ is lab-created using the skull melt process.

Uses & applications

Used primarily in fine jewelry (rings, earrings), industrial cutting/grinding for diamonds, and as diamond simulants in fashion jewelry for CZ.

Geological facts

Diamonds are the hardest known natural substance. Cubic Zirconia is a synthetic gemstone often substituted for diamond due to its high refractive index and lower cost.

Field identification & locations

Identify by testing thermal conductivity or checking for a 'read-through' effect. Diamonds are found in kimberlite pipes or alluvial deposits in Africa, Russia, and Canada.

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