Know the color.
Know the price.
Before you commit — the only gemstone color tool that uses a physical calibration card, peer-reviewed academic references, and an honest confidence band. So dealers, jewelers, and collectors know the color, know the price, and decide with confidence in minutes, not weeks.
how it works
Calibrate with the reference card
Print or load the serialized reference card. The camera locks onto the card’s alignment markers and builds a per-device color correction matrix — so the color you see is the color on the stone, not an artifact of your phone’s sensor or the room’s lighting.
Scan the stone before you commit
Place the stone in the card’s center target. In seconds, the engine measures body color in CIE L*a*b* — the same color space gemological labs use — runs a parallel perceptual model that accounts for how your eye adapts to the lighting, and returns an honest grade with a confidence band.
Decide with confidence
Get a traceable GemMetric™ grade linked to the card’s serial, matched against peer-reviewed academic centroids, and paired with a market price reference. Know the color, know the price — then decide whether to buy, sell, or walk away.
Why the industry needs it
- Honest color with a confidence band — not false precision
- Market price reference tied to the measured grade
- Serial-linked traceability the trade can verify
A single mis-graded ruby can swing $2,000–$10,000 in price. GemMetric is $19.99/mo.
Calibrated Color in Seconds
CIE L*a*b* colorimetry with a parallel perceptual model and an honest confidence band — know what you’re actually looking at, not what your phone guesses
Market Price Reference
See what stones of the same grade trade for — auction results, price trends, and trade data paired to your measured color so you know the number to negotiate
Trust You Can Verify
Every grade is serial-linked to a physical reference card and reproducible across devices — the trade can check your work, not just take your word
Built for the moment you decide
Color drives 50–80% of a colored stone’s value — and every transaction hinges on getting it right. GemMetric exists for the moments when you can’t wait for a lab report.
At the gem show
You have 90 seconds and no lab. The dealer names a grade and a price. Scan the stone against the card, get an honest color read with a confidence band, and know whether the grade — and the price — hold up before you shake on it.
At the supplier’s counter
A supplier hands you a stone at a price that assumes a specific color grade. GemMetric tells you in seconds whether the grade is real, whether the band is tight enough to trust, and what that grade actually trades for — so you negotiate from data, not memory.
From an online listing
You’re buying from a photo, blind to the stone in hand. The seller claims a grade; you can’t verify it. Scan the listing photo against the card, get a measured color and a market price reference, and decide whether the stone is worth the asking price — or the cost of a plane ticket to see it.
Why this isn’t just another color app
Every phone color tool picks the nearest hex code. GemMetric is built on a physical reference standard, academic science, and an honest confidence band — because the trade can’t afford false precision.
The eye
- —Fast, intuitive
- —Varies by grader, lighting, and fatigue
- —No record, no reproducibility
- —Two experts can disagree on the same stone
Swatch book
- —Industry standard for decades
- —Subject to lighting and print drift
- —Proprietary, paywalled references
- —Still a human judgment call
GemMetric™
- +Instrumental CIE L*a*b* measurement
- +Physical calibration card per scan
- +Peer-reviewed academic centroids
- +Honest confidence band + market price
Why now
Online gem sales are growing fast — buyers increasingly can’t hold the stone before committing, which makes the color call harder and the stakes higher. The transaction moved online before the tools caught up. GemMetric is the first calibrated, honest color read built for that world.
Built on peer-reviewed color science
Honest by design
Every grade carries an uncertainty band that tells you how much to trust it. False precision gets a tool fired after one bad call — honesty is what gets it re-used, and re-use is what builds trust in the trade.
Perceptual, not just measured
The engine runs a parallel color appearance model (CAM16) alongside the instrumental measurement, accounting for how the human eye adapts to different lighting — so a stone graded under warm LED and the same stone under daylight converge toward the same perceived color.
Tiered evidence you can see
Each reference is tagged peer-reviewed, industry, or estimated — so you always know the strength of the science behind a grade before you act on it. No black box, no proprietary swatch book behind a paywall.
Commit with confidence
Calibrate once. Grade any stone. Know the color, know the price, and decide with confidence — every result traceable to a serial-linked reference card.