What is troy ounce?
Short answer: A troy ounce is 31.1034768 grams and is the unit used to price gold, silver, platinum and palladium.
It is about 9.7% heavier than the everyday avoirdupois ounce of 28.3495 grams. There are 20 pennyweights or 480 grains in a troy ounce.
Try it: Gram to troy ounce converter