Grams in Troy Ounce

Ancient system of weights

The troy ounce is a unit of measure which goes back to the Middle Ages, when it was originally used in Troyes, France. It was used for measuring the weight of precious metals. This unit is not normally used in everyday life and hence the conversion can sometimes be difficult, as it involves numbers with a lot of decimals. It is always a problem when converting from one system to another, and one must be aware of the correct conversion factors, to know the equivalent weight in, say, grams in troy ounce.

Equivalent weights for easy conversion

The Troy system of weights derives its name from Troyes which is about 100 miles on the eastern side of Paris in France. This system of weights was then used as a standard form in the United Kingdom. The coins produced in the US mint also adopted the troy ounce as their standard unit, in the year 1828. But this troy ounce is different from the customary ounce of English units. There are 12 troy ounces in a troy pound, compared to the 16 ounces present in the standard pound. The smallest troy unit is the grain. There are 24 grains in a pennyweight and 20 pennyweights in a troy ounce. The weight of a troy pound is also equivalent to the apothecaries pound. The latter is quite different from the avoirdupois pound and ounce. One standard ounce or avoirdupois ounce is equal to 28.35 grams.

Troy ounce and grams

Grams belong to the metric system of weights while the troy ounce belongs to the troy weights system. In order to convert grams to troy ounce, the value of the troy ounce should be divided by .03215075. The troy ounce is heavier than one gram and one troy ounce is the equivalent of 31.1 grams approximately. Hence, if you know the weight of a precious metal in grams and want to convert the gram weight into troy ounces, then you can divide the number of grams by 31.1034768, which will give you the weight in troy ounces. For instance, if the item you weighed is 10 grams, then you should divide this by 31.1 and this gives you the weight as .3215 troy ounces.

In order to know grams to troy ounce conversion in a bar of gold or silver, there are 35.2 troy ounces in one kg of a gold bar, whereas Chinese gold bars, which are also known as tael bars have weights up to 12 troy ounces.

Want more information about gold and other precious metals? Visit our guide to Precious Metal.

Grams in Troy Ounce

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