Troy Ounce

Question: When is an ounce of gold not an ounce?

Answer: When it’s a troy ounce.

Ever since the Middle Ages people have been weighing precious metals such as gold, silver and platinum in troy ounces. It all started in Troyes, France where they got the idea from Roman times when many traders came from all over the known world to buy and sell goods. The Romans realized they needed a standard method to weigh and measure, so they would break bronze bars into 12 pieces that weighed a little over 31 grams each.

The practice carried on throughout the ages, so today there are 14.6 troy ounces in a pound compared to the usual 16. Here’s a trivia factoid that may come in handy the next time you are playing Tedium Pursuit or Scrabble: The official name of the standard ounce that’s used to weigh everything except precious metals is avoirdupois. So when you are buying or selling your gold jewelry, make sure the weight is listed as troy ounces, not standard ounces.