Stone / Non-Gold Weight Deduction Calculator
A piece is weighed with its stones or non-gold settings still attached. Enter the gross weight and the weight to deduct to see the net metal weight, its fine gold content, and a reference value — built for US jewellers and goldsmiths who need the deduction shown transparently, never absorbed silently into the purity math.
Stone / Non-Gold Weight Deduction Calculator
UnavailableChecking the platform reference…Enter the gross weight and the weight of any stones or non-gold material to deduct, then a karat, to see the net metal weight and fine gold weight — using the platform's reference Gold price or a price you enter yourself.
The as-weighed total, including any stones or settings
Leave blank for none — contributes zero
Checking the platform reference price… Net weight and fine gold weight are still shown below — switch to Manual price to enter your own and see a reference value.
Enter a gross weight to see the net metal weight and fine gold weight.
How this is calculated
Net metal weight = gross weight − stone/non-gold deduction. This is a physical measurement correction, computed before any purity math, and needs no market data at all.
Fine gold weight = net metal weight × purity fraction (14K = 14/24, and so on) — the same purity engine every other calculator on this platform uses, applied to the net weight rather than the gross weight.
Reference value is the fine gold weight multiplied by a Gold price, either the platform's verified reference price or one you enter yourself.
What net metal weight means
Net metal weight is the gross weight minus the weight of any stones or non-gold material. This is a physical measurement correction, applied before any purity math — not a percentage, not a charge, and not an estimate. A deduction greater than the gross weight is rejected outright, because a piece cannot contain a negative amount of metal.
Stone deduction, purity, wastage and melt value — kept distinct
Stone / non-gold deduction removes physical, non-metal mass from the gross weighed figure. Purity (karat) then reduces that net metal weight to its fine-gold content — it assumes the weight it is given is already 100% metal and alloy, never stone. Wastage and making charge are monetary charges added on top of a fine metal value for manufacturing loss and labor — not physical weight adjustments at all, and not part of this calculator (see the Making & Wastage Calculator for those). Melt value here is the reference value of the net metal content alone. None of this is an appraisal or a guaranteed buyer offer — what a specific buyer proposes to pay depends on that buyer.
Common US jewellery purities
US jewellery is most commonly stamped 10K, 14K, 18K, 22K or 24K. Karat states the fraction of pure gold out of 24 parts — 14K is 14/24 fine, for example — and this calculator applies that exact fraction, never a rounded approximation, to the net metal weight.
- 10K = 41.67% fine
- 14K = 58.33% fine
- 18K = 75.00% fine
- 22K = 91.67% fine
- 24K = 100.00% fine
What this calculator does not do
It does not add wastage, a making charge, a dealer margin, or any tax. It does not fabricate a Gold price either — when no verified platform reference is available, it says so plainly rather than substituting a stale, guessed, or placeholder figure, and Manual price mode still works with a price you supply. Net metal weight and fine gold weight need no market data and are always shown once a valid weight is entered.