What Is A Troy Ounce?
If you were to take 1 oz Gold coin from your personal collection and place it on a standard grocery-store scale, you would find that your coin is approximately 10% heavier than an ounce of beef or mushrooms or chocolate. Simply put, the two measures of an ounce are not the same. A troy ounce is approximately 10% heavier than an avoirdupois ounce.
As you begin buying and selling Gold, Silver, and other Precious Metals, you will notice that Precious Metals are weighed differently than other common items. Precious Metals are weighed using the traditional troy weight system as opposed to the more familiar “avoirdupois” units that we employ when weighing other goods.
Goods such as chocolate or sugar or coffee are measured using avoirdupois ounces. The name may sound odd to you unless you know French, but the word avoirdupois is literally translated as “goods of weight” and is simply the unit of measure we in the United States use to weigh almost everything other than Precious Metals.
A troy ounce is a bit heavier than a regular ounce. One standard ounce is 28.35 grams, while a troy ounce translates to 31.1 grams.
The origins of the Troy weight system may sometimes be debated, but it is commonly believed that the name is derived from Troyes, a trade market in France. Merchants converged on that area from all over the world to buy and sell goods, so a standardized unit of weight would have made doing business much more efficient. Later, many areas of Europe devised their own version of the troy ounce, but the French troy system is believed to be most closely related to the one that we still use today.
THE TROY OUNCE TODAY
Prior to the adoption of the metric system, French-born King Henry II of England chose to adjust the British coinage system to be more in line with the French troy system he felt was superior. The system was tinkered with periodically, but the troy weights we know today were first used in England during the 15th century. By 1527, the troy ounce had become the official standard measurement for Gold and Silver in Britain, with the U.S. finally adopting the troy system in 1828. Just like the worldwide traders in Troyes, France, buyers and sellers today need a standardized form of measurement for Precious Metals.