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Precious metals calculator
Value of gold, silver, platinum and palladium at market quotes, updated every 30 minutes on weekdays.
The calculator interface is in Spanish; the figures are universal.
How the calculation works
We multiply the weight of the piece by its purity (fineness) and by the metal price, converted to euros. The market quote updates every 30 minutes on weekdays; outside those hours the latest available is shown.
Values are indicative. The real buy/sell price depends on the buyer (jeweler, refinery, pawn shop) and usually includes a 10–25% margin over the pure metal value. It is not an official appraisal.
Need to estimate the weight of a mounted gem? Gem weight calculator →
Need to appraise the stones too and issue a report?
Start 14-day trial →How the price of gold per gram is calculated
Gold is quoted on international markets in dollars per troy ounce (31.1035 grams). To reach the price per gram in euros shown by this calculator, two conversions are made: ounce to gram and dollar to euro at the current exchange rate. On that pure metal price, the fineness of the piece is applied: an 18-karat gold ring contains only 75% gold, so it is worth three quarters of what it would weigh in fine gold.
It is worth distinguishing the spot price — the market quote you see here — from the real buy/sell price. No buyer pays the exact spot: jewelers, pawn shops and refineries apply a margin that usually ranges from 10–25% to cover assay, melting and profit. The spot is the objective reference for negotiating; the final price depends on who you negotiate with.
Types of gold: karats and fineness
Gold karats do not measure weight (that is carats for gems) but purity: 24 karats is practically pure gold. In Spain jewelry is mostly made in 18K — “750 fineness”, 750 thousandths of gold per thousand.
| Karats | Fineness (thousandths) | Gold content |
|---|---|---|
| 24K | 999 | 99.9% — fine gold, bullion and investment coins |
| 22K | 916 | 91.6% — historic coins and oriental jewelry |
| 18K | 750 | 75% — the Spanish jewelry standard |
| 14K | 585 | 58.5% — common in American and German jewelry |
| 10K | 417 | 41.7% — legal minimum to be called “gold” in the US |
| 9K | 375 | 37.5% — common in British jewelry |
Why the metal weight is not the jewel’s value
This calculator answers a single question: how much the molten metal is worth. But a jewel is almost never worth just that. The stones — a center diamond, calibrated sapphires — can multiply the value of the whole, and the workmanship, the signature or the age also count. Selling a piece with good gems “by weight” is the most common way to lose money without realizing it.
To value the whole piece — metal, stones and setting, with a declared criterion — is what the ValorGem appraisal report exists for, with the methodology of a practicing gemologist.
Frequently asked questions
- How often is the quote updated?
- Several times a day. Next to each price we indicate whether the quote is current or, due to any incident with the data provider, the last available one.
- Why does the price not exactly match other websites?
- Each source publishes the quote at different moments and with its own buy/sell spreads. Differences of around 1% between sources are normal and reflect data freshness, not errors.
- What is palladium and why is it quoted so high?
- A platinum-group metal, scarcer than gold, whose demand comes mostly from automotive catalytic converters. In jewelry it is used in white-gold alloys and as the main metal in some collections.
- Does this calculator count as an official appraisal?
- No. It is an indicative market reference. An appraisal valid for insurance or inheritance requires inspection of the piece and a report signed by a professional.