Gemstone Identifier: Identify Any Gemstone from a Photo
Upload a photo of a cut, rough, or polished gemstone. The AI examines color saturation, transparency, facet geometry, and surface luster to return the gem type, estimated clarity grade, probable carat range, and a market value estimate. Free. No signup.
Drop a gemstone photo here or tap to upload
JPG, PNG, WebP, HEIC • Max 50 MB • 1 free scan per day
Analyzing your gemstone…
How the Gemstone Identifier Works
Photograph the Gem
Place the gemstone on a white background under natural light. Use macro mode if your phone supports it. Avoid flash. It blows out facet detail and distorts color.
AI Reads the Visual Signals
The model measures hue, saturation, tone, transparency level, facet pattern, and surface luster. It compares these signals against a dataset of thousands of labeled gemstone images spanning rough, cabochon, and faceted specimens.
Review Your Results
You receive the gem type, color classification, estimated clarity range, probable carat bracket, and a general market value window. Results display in seconds.
What Is a Gemstone Identifier?
A gemstone identifier reads a photo of any cut, rough, or polished stone and returns the gem type, estimated clarity, probable carat range, and a market value window.
How AI Reads Gems
The model extracts hue, saturation, tone, transparency, facet geometry, and surface luster from a single photograph. It compares those signals against a labeled dataset of thousands of gemstone images spanning rough, cabochon, and faceted specimens. A ranked match comes back in seconds. The output includes the gem name, Mohs hardness, and a ballpark wholesale value. Accuracy is highest on common faceted stones under natural daylight.
The 4 Cs: What AI Can Assess
Color is the strongest signal from a photo. The AI measures hue angle, saturation percentage, and tonal depth when white balance is correct. Cut shape (brilliant, oval, cushion, cabochon) is recognized from overhead. Clarity is harder. Surface-reaching fractures and large clouds show up, but subtle internal inclusions need 10x magnification. Carat weight is estimated from apparent size relative to standard dimensions for the identified gem type.
Precious vs. Semi-Precious
Only diamond, ruby, sapphire, and emerald carry the "precious" label. Every other gem is classified as semi-precious. The distinction is historical, not scientific, and it misleads regularly. Alexandrite, a semi-precious stone, exceeds $50,000 per carat for top specimens. Paraiba tourmaline sells for more than most sapphires. Ruby and sapphire (hardness 9) and diamond (hardness 10) do share exceptional durability for daily wear.
Common Treatments
Most gemstones sold today have been treated. Heat treatment is standard for sapphires, rubies, tanzanite, and aquamarine, and it does not drastically reduce value when disclosed. Fracture filling with glass, resin, or oil is common in emeralds and rubies but lowers value significantly. Irradiation produces blue topaz from colorless material. No photo-based tool can detect these treatments. That requires a gemological microscope, spectrometer, or UV fluorescence test.
Photographing Gemstones
Use natural daylight from a north-facing window. Direct sunlight creates hot spots on facets that wash out color data. Flash introduces white-balance errors and makes transparent stones look opaque. Place the gem on a white or light gray surface so transmitted light stays visible. Macro mode captures facet detail at close range. A steady hand or propped phone prevents the blur that drops identification accuracy the most.
Synthetic vs. Natural
A lab-grown ruby and a mined ruby share the same chemical composition, crystal structure, and visual appearance. The differences are specific inclusion types and growth patterns visible only under magnification with proper lighting. No photograph reveals these. High-quality synthetics exist for ruby, sapphire, emerald, alexandrite, and diamond. If origin matters for your purchase, only a certified gemological lab can separate natural from synthetic.
Rough Gemstones
Uncut stones lack the facets and polished surfaces that make identification straightforward. The AI relies more on color, crystal habit, and surface texture for rough specimens. Wetting the surface before photographing fills micro-scratches and temporarily restores the optical properties that polishing would create. Color and transparency become much more visible. This single step improves accuracy on rough material more than any other factor.
Limitations
AI cannot measure refractive index or specific gravity from a photo. These physical tests separate lookalikes that appear identical on screen. Origin cannot be assessed either, and a Kashmir sapphire differs dramatically in price from a Madagascar sapphire of similar appearance. Use this tool as a fast first pass. For purchase decisions or insurance appraisals, follow up with a certified gemologist. The crystal identifier and Lens App offer alternative tools for narrower categories.
Frequently Asked Questions
How can I identify a gemstone at home?
Photograph it in natural light against a white background and upload the image to the scanner above. For a definitive ID, a gemologist uses a refractometer and microscope.
What gemstone is this?
Upload a photo to the scanner above. The AI reads color, transparency, cut shape, and luster to return the most likely match.
Can AI tell if a gemstone is real or synthetic?
No. High-quality synthetics are visually identical to natural stones. Lab equipment is required to separate them.
What are the most valuable gemstones?
Ruby, blue sapphire, emerald, alexandrite, and padparadscha sapphire typically command the highest prices per carat. Value depends on color saturation, clarity, size, and treatment status.
How do I tell the difference between ruby and garnet?
Ruby is hardness 9, garnet is 6.5 to 7.5. Ruby fluoresces under UV light while most garnets do not. Color alone is unreliable.
Is there a free gemstone identifier app?
Yes. Rock Identifier is free on iOS and Android, and the web scanner at rockidentifier.io offers one free scan per day.
What are the 4 Cs of gemstones?
Cut, color, clarity, and carat weight. Together they determine a gemstone's market value.
Can I identify an uncut gemstone from a photo?
Yes, but accuracy drops compared to faceted stones. Wetting the surface before photographing helps the AI read color and transparency.
What is the difference between precious and semi-precious gemstones?
Only diamond, ruby, sapphire, and emerald are classified as precious. Everything else is semi-precious, though some semi-precious stones sell for far more per carat.
Does gemstone color affect value?
Color is usually the single most important factor. A pigeon-blood ruby is worth dramatically more than a pinkish-red one of the same size.