Gross weight is not fine-metal weight.
Start with the scale’s unit. Grams, pennyweight and troy ounces are different measures. One troy ounce is 31.1034768 grams; one pennyweight is one twentieth of a troy ounce.
Subtract non-metal weight before applying the alloy’s purity. In a hypothetical 8.40 g ring with a 1.20 g non-metal deduction, 7.20 g remains as the alloy weight. At a 0.750 purity fraction, that represents 5.40 g of fine metal.
Match the quote to the metal.
Divide fine grams by 31.1034768 to obtain fine troy ounces. Multiply those ounces by the appropriate metal’s price per troy ounce, in the currency being used.
A quote needs a source and timestamp. A saved original quote can explain an earlier estimate; a new offer needs a current, permitted quote. Never price silver or platinum against a gold quote because the purity fraction happens to look familiar.
Recovery and buying assumptions do different work.
| Input | Question it answers |
|---|---|
| Recovery rate | How much of the modeled metal value is expected to be recoverable? |
| Refiner discount and fees | What deductions apply before deciding the offer? |
| Buying factor | What share of the modeled net value is being offered? |
| Resale assumption | What formula-based reference is used for the finished piece? |
| Rounding | At which point are payable money values reduced to currency precision? |
The browser preview uses sample recovery and offer assumptions that you can inspect. The production app’s current default calculation has its own assumptions. Do not treat a demonstration percentage as your shop’s approved buying policy.
Keep enough to understand the decision later.
- Item and customer reference.
- Gross weight and unit, non-metal deduction and purity fraction.
- Metal quote, source, timestamp and currency.
- Recovery, fee and buying assumptions.
- Saved outputs and when the estimate was made.
- The reason for a revised estimate, kept distinct from any signed agreement or payout.
Open the interactive buying desk and change one input at a time. It is a quick way to see which parts of the offer move and which questions still require a buyer’s judgment.