mineral
Ruby (Raw Corundum)
Corundum (Al2O3) with Chromium traces
AI-generated identification · may be incorrectHardness: 9 on Mohs scale; Color: Red to deep purplish-red; Luster: Adamantine to vitreous; Crystal structure: Trigonal/Hexagonal; Cleavage: No true cleavage (displays parting); Specific gravity: 3.97-4.05
- Hardness
- 9 on Mohs scale
- Color
- Red to deep purplish-red
- Luster
- Adamantine to vitreous
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Physical properties
Hardness: 9 on Mohs scale; Color: Red to deep purplish-red; Luster: Adamantine to vitreous; Crystal structure: Trigonal/Hexagonal; Cleavage: No true cleavage (displays parting); Specific gravity: 3.97-4.05
Formation & geological history
Formed in metamorphic rocks seperti schists, gneisses, and marbles through contact or regional metamorphism of aluminum-rich sediments. Also found in igneous rocks such as syenite.
Uses & applications
Used primarily in high-end jewelry as a gemstone, industrial abrasives due to hardness, and historic use in ruby lasers.
Geological facts
Ruby is the red variety of the mineral corundum; every other color is called sapphire. It is second only to diamonds in terms of natural mineral hardness.
Field identification & locations
Identify by its hexagonal barrel shape (prisms), extreme hardness, and purplish-red hue. Commonly found in Myanmar (Burma), Madagascar, Thailand, and Mozambique.
