gemstone

Polished pink corundum (likely treated ruby)

Corundum, aluminum oxide (Al₂O₃); ruby when red-to-pink from chromium

AI-generated identification · may be incorrect

Hardness 9 Mohs; vivid pink-red color, vitreous luster, translucent appearance, and trigonal crystal structure. The rounded, glossy surface indicates a polished or tumbled specimen; inclusions and color zoning are visible.

Identified September 21, 2026More gemstone →

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At a glance

Common name: Polished pink corundum (likely treated ruby)
Scientific name: Corundum, aluminum oxide (Al₂O₃); ruby when red-to-pink from chromium
Category: gemstone
Identified: September 21, 2026
Method: Standard

AI Estimated Value

About $5–$30 for a small polished commercial piece; $50–$500+ if natural, untreated, transparent, and gem-quality; synthetic or heavily treated material is usually inexpensive.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Forms in aluminum-rich, silica-poor metamorphic rocks and some igneous settings through high-temperature geological processes. Natural corundum crystals formed over varied Precambrian-to-younger ages; treatment or synthetic origin cannot be determined from the image.

Uses & applications

Used as an abrasive and, when transparent and attractive, as ruby jewelry or a collector gemstone. Pink material is often sold as pink sapphire or treated ruby depending on hue and certification.

Geological facts

Ruby and sapphire are color varieties of corundum; red coloration is chiefly caused by chromium, while pink shades may involve lower chromium concentrations.

Field identification & locations

Confirm with hardness, refractive-index, and laboratory testing; glass, dyed quartz, and synthetic corundum can look similar. Common sources include Myanmar, Sri Lanka, Mozambique, Tanzania, and Madagascar.