gemstone

Diamond

Carbon (C)

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal Structure: Isometric (cubic), Cleavage: Perfect octahedral, Specific Gravity: 3.52

Identified July 17, 2026More gemstone →

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Physical properties

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal Structure: Isometric (cubic), Cleavage: Perfect octahedral, Specific Gravity: 3.52

Formation & geological history

Formed deep within the Earth's mantle under extreme pressure and high temperatures, then transported to the surface by volcanic eruptions of kimberlite and lamproite magmas. Age ranges from 1 to 3.5 billion years.

Uses & applications

Primary use in high-end jewelry (engagements, fashion) and critical industrial applications such as cutting, grinding, and drilling tools due to extreme hardness.

Geological facts

Diamond is the hardest naturally occurring substance known. The 'Four Cs' (Cut, Color, Clarity, and Carat Weight) determine its gemstone quality and value. It is the birthstone for April.

Field identification & locations

Identified by its high refractive index (brilliance) and unique hardness. In the field, look for octahedral crystals within kimberlite pipes or as alluvial deposits in riverbeds. Professional appraisal is necessary to distinguish from stimulants like cubic zirconia.