Gold, silver and other precious metals are weighed in troy ounces rather than grams or the typical avoirdupois ounce. The troy ounce is said to derive from a weighing system developed in Troyes, France, during the Middle Ages. A troy ounce equals 31.1 g, whereas the avoirdupois ounce used in the United States equals 28.35 g. Using this knowledge, you can convert any weight of gold or silver measured in grams to avoirdupois ounces or troy ounces.

## Grams to Troy Ounces

Enter the number of grams of gold or silver you have into your calculator. For this example, consider 100 g of gold.

Press the division sign. Enter "31.1" -- the number of grams in a troy ounce.

Press the total sign ("=" on most calculators). The result is how many troy ounces of gold or silver you have. For the example, there are 3.22 troy ounces of gold (100 / 31.1 = 3.22).

## Grams to Avoirdupois Ounces

Enter the number of grams of gold or silver you have into your calculator. For this example, you have 100 g of silver.

Press the division sign. Enter "28.35" -- the number of grams in an avoirdupois ounce.

Press the total sign ("=" on most calculators). The result is how many avoirdupois ounces of gold or silver you have. In the example, there would be 3.53 avoirdupois ounces of silver (100 / 28.35 = 3.53).