Gram
Also: g, Gram (g)
The gram (unit symbol g) is the base unit of mass in the International System of Units (SI) and the world's most commonly used weight unit in precious metals trading.
The gram is the smallest standard unit of mass in the International System of Units (SI) and equals one thousandth of a kilogram. In precious metals trading the gram has special significance: small bars (1 g, 2 g, 5 g, 10 g), dental gold purchases and melt value calculations are stated almost without exception in grams. With the melt value calculator, the material value of scrap gold or silver jewellery can be determined to the second on a per-gram basis.
The gram in relation to other precious metal weight units
Internationally, gold is traded on the major marketplaces (LBMA, COMEX) not 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 into grams is the first step to a price assessment for private investors.
| Unit | Grams (g) | Region of use |
|---|---|---|
| 1 troy ounce (troy oz) | 31.1035 g | World 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 |
You can calculate the current gold price per gram by dividing the troy-ounce price by 31.1035 - or you can use the gold calculator directly, which performs this conversion automatically.
The gram as a trading unit for bars and coins
Small bars of gold and silver are offered in Europe as standard in gram weights:
- 1 g, 2 g, 5 g - entry bars, often in credit-card format (e.g. CombiBar)
- 10 g, 20 g, 31.1 g (= 1 oz) - medium denominations for building savings
- 50 g, 100 g - common investment bars with reduced premium compared to the smallest bars
- 250 g, 500 g, 1 000 g (= 1 kg) - larger trading bars
The smaller the bar in grams, the higher as a rule the premium (agio) relative to the pure material value. A purchase price calculator shows what value dealers pay for a given gram weight.
Formula box: gram conversions
Price per gram = troy-ounce price / 31.1035
Fine weight (g) = gross weight (g) x fineness (‰ / 1000)
Melt value (EUR) = fine weight (g) x gold price per gram (EUR/g)
Significance in scrap gold and dental gold buying
When buying dental gold, old jewellery or broken gold, the gram is the central calculation unit. What is decisive here is not the gross weight but the fine weight: a 14-carat bracelet with a total weight of 10 g contains, notionally, only 5.85 g of fine gold (fineness 585 ‰). The silver calculator works on the same principle for silver objects.
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 place any melt value and any dealer price in context.