Gross Weight
Also: Brutto weight, Total weight, Raw weight
The gross weight is the total weight of a precious metal object including all alloying components, before any deduction for impurities or additives.
The gross weight denotes the complete physical weight of a precious metal object - that is, the weight a scale displays, without any deduction for alloying components, impurities or foreign material. It stands in direct contrast to the fine weight, which describes only the actual precious metal content. Anyone who wants to determine the value of gold jewellery, coins or scrap silver must know this distinction.
Gross weight and fine weight in relation
The relationship between gross weight and fine weight can be described with a simple formula:
Fine weight = gross weight x fineness (as a decimal)
The fineness indicates what proportion of the gross weight consists of pure precious metal. In a gold alloy stamped 585 (14 carat), 58.5% of the gross weight is pure gold; the remaining 41.5% is made up of alloying metals such as silver, copper or zinc.
| Alloy | Hallmark | Fineness | Fine weight at 10 g gross weight |
|---|---|---|---|
| 8-carat gold | 333 | 33.3% | 3.33 g |
| 14-carat gold | 585 | 58.5% | 5.85 g |
| 18-carat gold | 750 | 75.0% | 7.50 g |
| 22-carat gold | 916.7 | 91.67% | 9.17 g |
| Fine gold | 999 | 99.9% | 9.99 g |
| Sterling silver | 925 | 92.5% | 9.25 g |
| Cutlery silver | 800 | 80.0% | 8.00 g |
Practical significance for buying and melt value
Dealers, refineries and pawnbrokers always quote prices on the basis of the fine weight, not the gross weight. Anyone selling scrap gold or silver jewellery therefore only receives the value of the precious metal actually contained. With the melt value calculator, the material-value-based amount can be calculated directly from gross weight and hallmark - the dealer's buying price is usually below this, since processing costs and margin are deducted.
Key steps in value determination:
- Determine the gross weight on a calibrated fine scale (accuracy >= 0.01 g).
- Read the hallmark or punch mark and establish the fineness.
- Calculate the fine weight: gross weight x fineness.
- Multiply the fine weight by the current gold price or silver price.
Gross weight in coins and bars
For certified bullion coins and LBMA Good Delivery bars, gross weight and fine weight are precisely defined and stated on the product. A one-troy-ounce Krugerrand, for example, contains exactly 31.1035 g of fine gold (one troy ounce), but as a coin weighs around 33.93 g - the additional weight comes from the copper content (fineness 916.7/1000; 22 carat). The gross weight is therefore measurably greater than the fine weight here.
For fine bars (999.9), by contrast, gross weight and fine weight are almost identical; the minimal difference lies within the manufacturer's permitted tolerance limits.
Distinction from related terms
- Fine weight: The calculated precious metal content within the gross weight.
- Brutto weight (in a trade context): May additionally include packaging or containers - not to be equated with gross weight, although both terms are used interchangeably in everyday language.
- Troy weight: The weight system used internationally in the precious metals trade; one troy ounce equals 31.1035 g.
In brief
The gross weight is the starting figure for every precious metal valuation - only by multiplying it by the fineness do you arrive at the value-relevant fine weight. Anyone buying or selling jewellery, coins or bars should always keep the two figures clearly separated and always apply the current metal price to the fine weight.