Gram
Also: g, Gram (g)
The gram (symbol g) is the base unit of mass most people work with under the International System of Units (SI) and the most widely used weight unit in the precious-metals trade.
The gram is the smallest standard unit of mass in everyday use under the International System of Units (SI) and equals one thousandth of a kilogram. In the precious-metals trade the gram carries particular weight: small bars (1 g, 2 g, 5 g, 10 g), scrap-gold purchases and melt-value calculations are almost always expressed in grams. With the melt value calculator you can work out the material value of scrap gold or silver jewellery down to the second on a per-gram basis.
The gram against other precious-metal weight units
Internationally, gold on the major trading venues (LBMA, COMEX) is not quoted in grams but in the troy ounce (ozt). One troy ounce equals exactly 31.1034768 grams. Because the spot price is always expressed in troy ounces, converting to grams is the first step to sizing up a price as a private investor.
| Unit | Grams (g) | Region of use |
|---|---|---|
| 1 troy ounce (troy oz) | 31.1035 g | Global market (LBMA, COMEX) |
| 1 kilogram | 1,000 g | Europe, large bars |
| 1 tola | 11.6638 g | India, Pakistan |
| 1 tael (Hong Kong) | 37.4290 g | China, East Asia |
| 1 pennyweight (dwt) | 1.5552 g | US jewellery industry |
| 1 grain (troy) | 0.06480 g | Historical, numismatics |
| 1 momme | 3.7500 g | Japan |
Work out the current gold price per gram by dividing the troy-ounce price by 31.1035 — or simply use the gold calculator, which handles the conversion automatically.
The gram as a trading unit for bars and coins
Small gold and silver bars are sold in Europe as a matter of course in gram weights:
- 1 g, 2 g, 5 g – entry-level bars, often in credit-card format (e.g. CombiBar)
- 10 g, 20 g, 31.1 g (= 1 oz) – mid-range denominations for building up a position
- 50 g, 100 g – common investment bars with a lower premium than the tiniest bars
- 250 g, 500 g, 1,000 g (= 1 kg) – larger trade bars
The smaller the bar in grams, the higher the premium relative to the pure material value tends to be. A purchase price calculator shows what dealers will pay for a given gram weight.
Formula box: gram conversions
Price per gram = troy-ounce price ÷ 31.1035
Fine weight (g) = gross weight (g) × fineness (‰ ÷ 1000)
Melt value (€) = fine weight (g) × gold price per gram (€/g)
Relevance in scrap-gold and dental-gold buying
When buying dental gold, old jewellery or broken gold, the gram is the central unit of calculation. What matters is not the gross weight but the fine weight: a 14-karat bracelet weighing 10 g in total contains just 5.85 g of fine gold (fineness 585 ‰). The silver calculator works on the same principle for silver items.
In brief
The gram is the universal working unit in the European precious-metals trade — from the 1 g gold card to the 1 kg bar. Anyone who knows the current per-gram price and keeps the simple conversion formula (troy-ounce price ÷ 31.1035) in mind can quickly size up any melt value or dealer price.