An ancient system of weights
The troy ounce belongs to the Troy weight system, which contains troy ounce, troy pound, drams and scruples. The troy pound is not often used, but the troy ounce is the common way of reporting the prices of precious metals. A troy ounce is used to measure weights of precious metals, but it may be necessary to convert it into other systems such as the metric system. For this, one needs to know the metric equivalents, for proper conversion and value estimation. In order to get the value of grams per troy ounce, the troy ounce needs to be multiplied by 31.103 as a troy ounce is heavier than a gram by about 31 times.
Converting into the metric system
There are thus 31 grams in a troy ounce. In case you wish to convert grains into grams, then there are 64.799 milligrams in one grain. For converting pennyweights into the metric system, you need to multiply the value of the pennyweight by 1.555 and you will get the value in terms of grams. If you want to calculate the value of the pennyweight in milligrams, it should be multiplied with 1555 (1.555×1000). For calculating the value of 1 troy pound in the metric system, you need to multiply the troy pound weight with 373.242 in order to get the equivalent in grams. In case of getting the value in kilograms, then the value of the troy pound should be multiplied with 0.373242.
At times, the weight of a particular precious metal may be given in milligrams, which belongs to the metric system. If you wish to convert this value to the troy system, this too can be done. A milligram is a much smaller value than a troy ounce, and hence the milligram value should be multiplied by 0.00003215 in order to obtain its value in troy ounces. Another method of doing this would be to divide the number of milligrams by 31,104.199. This means that there are about 32,000 milligrams in a troy ounce.
Grains and Troy ounce
After finding out how many grams per troy ounce, you may further want to know how many grains are there in a troy ounce. A grain is used as a unit of measurement, where the weight is equivalent to one seed of that cereal in its typical form. If you are given the weight in grains, then you need to divide the grain value by 480 in order to get the value of the item in troy ounces. This is because there are 480 grains in a troy ounce.
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