There are 12 troy ounces in a pound. The troy weight system has been used since the Saxon times, and itÂ was supposed to directlyÂ mimic the Roman measurement system. Currently, troy weight is used for precious gems and metals.
One troy ounce equals 480 grains. The more standard measuring system uses 437.5 grains per ounce. This is the amount that is used to measure a standard pound, which has 16 ounces in it. The troy ounce became focused on metals and gemstones because of the difficulty to convert it for standard everyday use. The regular measuring system was much simpler to use for regular conversions used at the home and in the work place.