Gemstones
Cabochon Weight Calculator
Estimate cabochon weight in carats, grams, and points from mm dimensions using shape, dome profile, and specific gravity (SG).
Cabochon Weight Estimator (MM → Carat / Gram)
Estimate cabochon weight by shape with dome and SG adjustments, plus round-mode and total weight for quantities.
This calculator estimates volume from idealized geometry and a dome ratio, then multiplies by specific gravity to estimate weight. Real cabochons differ by bevel, base curvature, dome shape, and finishing. For exact weight, use a scale.
Round cabochons use diameter as both length and width, with a circular base area coefficient. If the base is slightly oval, use the shape tab and enter both length and width.
Quantity totals are useful for parcel planning, production estimates, shipping weights, and comparing rough yield assumptions. If you are producing cabochons, you can add a percentage allowance to approximate variability or breakage.