Troy Ounce vs. Ounce

Differing values

In all commodity markets and trading websites, we find that precious metals are weighed in the form of troy ounces, though at times, they just mention the term ounce. The investor must be careful to distinguish the values of a troy ounce vs ounce, as there is a slight difference between the two weight measures. Normal commodities like sugar, rice and other grains are measured in the common ounce at groceries and are known as the avoirdupois ounce.

The common ounce

All your everyday weighing in English speaking countries, like the US and the UK is done in the form of ounce or avoirdupois ounce. This is the way we measure our weight when stepping on the weighing scale or for weighing the food in groceries and markets. An avoirdupois ounce has a slightly lesser weight than the troy ounce. A pound has 16 avoirdupois ounces in it. In terms of grams, 1 avoirdupois ounce contains 28.35 grams. Weights are also measured in terms of what are known as grains, and an avoirdupois ounce contains 437.5 grains in it. From the above relations, we can also derive a relation between the avoirdupois pound and grams, with an avoirdupois pound equivalent to 16×28.35 grams that is 453.6 grams. With respect to its relation to troy ounce, one avoirdupois pound is equal to 14.583 ounces.

Conversion methods

On the other hand, when we compare the troy ounce vs ounce, we see that the form is heavier and hence if you buy silver or gold coins, then you receive one troy ounce, which is about 10% heavier than the common ounce. One troy ounce is the equivalent of 1.1 avoirdupois ounces. In case you want to relate the troy ounce to grams, then one troy ounce is equal to 31.1 grams. In the troy weights, we also have the troy pound. The troy pound contains 12 troy ounces in it. Thus, we can derive the relation between troy pound and grams. One troy pound contains 12×31.1 grams, that is to say, 373.24 grams in it. This value of grams present in a troy pound is roughly equal to about 13 avoirdupois ounces.

The troy system of weights is considered to have got its name after the Troyes of France, sometime during the Middle Ages. The troy system also contains another smaller measure in it known as pennyweights. When comparing the troy ounce vs ounce, one troy ounce contains 20 pennyweights in it. You can also derive the relation in terms of kilograms, with a kilogram equal to 1000 dived by 31.1 troy ounces, which is equivalent to 32.15 troy ounces.


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Troy Ounce vs. Ounce

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