gemstone

Ruby (Faceted)

Corundum (Al2O3:Cr)

Hardness: 9 on the Mohs scale. Color: Vivid red (pigeon blood). Luster: Adamantine to vitreous. Crystal structure: Trigonal/Hexagonal. Cleavage: None (has parting). Specific gravity: 3.97–4.05.

Hardness: 9 on the Mohs scale
Color: Vivid red (pigeon blood)
Luster: Adamantine to vitreous

Identified July 21, 2026More gemstone →

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Physical properties

Hardness: 9 on the Mohs scale. Color: Vivid red (pigeon blood). Luster: Adamantine to vitreous. Crystal structure: Trigonal/Hexagonal. Cleavage: None (has parting). Specific gravity: 3.97–4.05.

Formation & geological history

Metamorphic or magmatic origin. Natural rubies form under high pressure and heat in marbles or basaltic rocks, often millions of years old. Note: This item appears to be a high-clarity faceted stone, which could be natural, lab-grown, or a high-quality imitation (simulant).

Uses & applications

Primarily used in high-end jewelry (rings, necklaces), collection, and and industrial applications for synthetic variants (lasers, watch bearings).

Geological facts

The red color is caused by trace amounts of the element chromium. It is the birthstone for July and one of the four traditional 'precious' stones alongside diamond, sapphire, and emerald.

Field identification & locations

Identification includes looking for silk inclusions (natural) vs breath-like curved striae (synthetic) or air bubbles (glass simulant). Authentic rubies are extremely hard, second only to diamonds.