Why is a troy ounce different than an ounce?
Why is a troy ounce different than an ounce? A troy ounce is 1/12 of a troy pound (a troy pound is actually lighter than an avoirdupois pound). The troy ounce (480 grains) is heavier than the avoirdupois ounce (437.5 grains). This measures out to be about 10 percent more than the avoirdupois ounce, which is 28.349523125 g. How many regular ounces are in a troy ounce? 31.103 Troy ounce (oz t) A troy ounce weighs 480 grains. Because of the International yard and pound agreement, it may be inferred that one troy ounce (oz t) equals exactly 31.1034768 grams....