gemstone

Cut diamond tennis-chain jewelry

Diamond, crystalline carbon (C), cubic crystal system

AI-generated identification · may be incorrect

Likely faceted, near-colorless diamonds mounted in metal; hardness Mohs 10, adamantine luster, excellent brilliance, no visible cleavage at this scale. Exact identity, treatments, and metal cannot be confirmed visually; stones may be simulants.

Identified September 11, 2026More gemstone →

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Physical properties

Formation & geological history

Natural diamonds formed deep in Earth’s mantle under extreme pressure and temperature, commonly 1–3 billion years ago, then brought upward by kimberlite or lamproite eruptions; laboratory-grown diamonds have the same composition but a different origin.

Uses & applications

Jewelry, especially tennis chains and pendants; industrial diamond is used for cutting, grinding, drilling, and polishing. Value depends strongly on total carat weight, color, clarity, cut, provenance, and mounting metal.

Geological facts

Diamond is the hardest natural mineral, though hardness varies by crystal direction; it is not indestructible because cleavage can cause chipping. Reliable identification requires gemological testing for thermal conductivity, refractive properties, and inclusions.

Field identification & locations

Common natural sources include Botswana, Russia, Canada, Australia, and southern Africa. Inspect facet sharpness and inclusions, but use a reputable gemologist or laboratory report to distinguish diamond from cubic zirconia, moissanite, or glass.