gemstone

Ruby (cushion-cut red gemstone)

Corundum, Al₂O₃; red color is typically caused by chromium

AI-generated identification · may be incorrect

Mohs hardness 9; vivid red, vitreous luster, trigonal crystal structure, no true cleavage. The image shows a faceted cushion-cut stone, but its identity and natural or synthetic origin cannot be confirmed from appearance alone.

Identified September 29, 2026More gemstone →

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At a glance

Common name: Ruby (cushion-cut red gemstone)
Scientific name: Corundum, Al₂O₃; red color is typically caused by chromium
Category: gemstone
Identified: September 29, 2026
Method: Standard

AI Estimated Value

Highly variable: roughly $50–$500 for small or commercial-quality stones, while fine natural rubies can sell for thousands to millions of dollars; image alone cannot establish value.

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

Ruby forms when aluminum-rich rocks undergo high-temperature metamorphism or in some igneous settings; deposits range from ancient to geologically recent. The pictured stone has been cut and faceted.

Uses & applications

Used in fine jewelry and, because of its hardness, in specialized watch and industrial components.

Geological facts

Ruby and sapphire are both gem-quality corundum; the color distinction is largely due to trace elements.

Field identification & locations

Natural rubies occur notably in Myanmar, Mozambique, Madagascar, and Sri Lanka. Identification requires gemological testing; inclusions, chromium spectroscopy, and lab reports help distinguish natural from synthetic stones.