Gold, platinum, and silver content is always listed as troy ounces (also known as apothecary ounces), not the common U.S. avoirdupois ounces. A troy ounce is 31.10348 grams, versus an avoirdupois ounce which is 28.34952 grams. So when you buy an ounce of gold you are really buying slightly more than an ounce of gold. Don't let this bother you, though; unless you are manufacturing gold items you don't need to worry. Gold prices and content are all listed based on troy ounces, so you never have to convert (except sometimes grams to troy ounces).
Note that these contents factor in the fineness of the gold. For example, US gold coins are 22 karat, whereas Canadian gold coins are 24 karat. The US gold coin is approximately 92% gold whereas the Candian coin is 99.99% gold. Therefore, a US gold coin with the same gold content as a Canadian gold coin will be slightly larger and heavier (since it contains the same amount of gold as the Candian coin, plus some other metals). Although the US coin will be heavier, it will be listed as having the same gold content as the Canadian coin.
Note that you can use the "Update Spot" button to change the spot value used in the calculations to determine melt value!
| Coin | Gold Content | Melt value (if gold at $ ) |
|---|
Conversions: Weight/mass 1 grain = 0.06479891 grams 1 pennyweight = 24 grains = 1.55517384 grams 1 troy ounce = 480 grains = 20 Pennyweight = 31.1034768 grams 1 troy pound = 5760 grains = 373.2417216 grams = 12 troy ounces Purity 24 Karat = 100% Pure = .9999 Fine 22 Karat = 92% Pure = .9166 Fine 18 Karat = 75% Pure = .7500 Fine 14 Karat = 58% Pure = .5833 Fine 10 Karat = 42% Pure = .4166 Fine