One Troy Ounce

Origin of the Troy system

The name troy ounce comes from the troy weight system which was used in Troyes, a French city. It is used in the measurement of precious stone, as also for weighing gunpowder, gems, and arrows and so on. One must have a good idea of the troy system of weights as also the value of 1 troy ounce in terms of other systems of weights, in order to know the value of precious metals and follow the prices given for them in commodity markets.

Easy Conversions of measures

For instance, you should know the other weights in this troy system, such as troy pound and pennyweights. Obtaining the number of troy ounces in a metal can be done if the weight is given in the form of avoirdupois ounces, grams, grains, kilograms, avoirdupois pounds, troy pounds, pennyweights, and so on. For instance, if you have the weight in grains, then you need to multiply the number by 24 in order to obtain the weight in pennyweights. The abbreviated form of pennyweights is dwt. There are 24 grains in one pennyweight. This pennyweight value can be converted into troy ounces by dividing it by 20. This is because one troy ounce contains 20 pennyweights in it. From this, we see that there are 20×24, that is, 480 grains in one troy ounce.

For further conversion of the troy ounce value into troy pounds, you should divide the troy ounce number by 12, as one troy pound contains 12 troy ounces in it. This will lead you to another relation between pennyweights and troy pounds, that is, there are 240 (12×20 pennyweights in a troy pound. If you want a relation between grains and a troy pound, then a troy pound contains 5760 grains in it (12x20x24).

The two types of ounces

Additionally, you must also learn to distinguish between the ordinary pound used in groceries, which is known as the avoirdupois ounce or just ounce. The troy pound is shortened to lb t and the troy ounce is shortened to oz t. If you wish to convert the ordinary ounce or avoirdupois ounce into troy ounce, then the value of the avoirdupois ounce should be multiplied by 0.911 in order to obtain its equivalent in 1 troy ounce. But if you wish to convert a troy ounce into avoirdupois ounce, then you need to multiply it with the opposite or reverse, which is 1.098. This is because, the weight of the troy ounce is slightly more than the weight of the avoirdupois ounce.


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One Troy Ounce

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