Why troy ounces

A troy ounce is, in fact, a different unit of measurement than a standard ounce also called a avoirdupois ounce. One troy ounce equals 1. So why do we use troy ounces to measure the weights of certain metals? The troy ounce is believed to have originated in a French town called Troyes in the Middle Ages.

In the early s, the troy ounce was accepted as the official standard of measure for gold and silver in Britain, with the US adopting this measurement method as well in The troy ounce is the only unit of measure from the troy weight system that we still use, and it remains the standard at most sovereign and private mints.

The troy ounce is often abbreviated to read "t oz" or "oz t. Some historians believe the troy ounce had its origins in Roman times. Romans standardized their monetary system using bronze bars that could be broken down into 12 pieces called "uncia" or ounce, with each piece weighing around As Europe's economic importance grew from the 10th century onward, merchants came from all over the world to buy and sell goods there.

It was, therefore, necessary to develop a new standardized monetary weight system to make doing business much easier. Some believe the merchants of Troyes modeled this new monetary system using the same weights as their Roman ancestors. The troy ounce is the only measure of the troy weighting system that is still used in modern times. It is used in the pricing of metals, such as gold, platinum , and silver.

The system was adjusted periodically, but troy weights, as we know them today, were first used in England in the 15th century. Before the adoption of the troy system, the British used an Anglo-Norman French system called the avoirdupois system, which means "goods of weight" and was also used to weigh both precious metal and non-precious metal items.

By , the troy ounce became the official standard measurement for gold and silver in Britain, and the US followed suit in The avoirdupois ounce, simply referred to as ounce oz , is a metric commonly used in the US to measure foods and other items, except precious metals. It is the equivalent of A troy ounce is a little heavier, with a gram equivalent of The difference 2.

Because a troy ounce is heavier than a standard ounce, there are This pound is not to be confused with a troy pound, which is lighter and is made up of 12 troy ounces. The Royal Mint. Last Name. Phone Number. Retype Password. Already Have An Account? Log In. Email Address. Your Password. Remember Me Forgot Password? New to JM Bullion? Create An Account Track an Order? Check Order Status.

Reset Your Password. Enter your email address and we will send you a link to reset your password. Send Password Reset Email. Or Return to Log in. What Is Backwardation and Contango? Why are Silver Coins Different Prices? How is the Gold Spot Price Set? How is the Silver Spot Price Set? How is the Platinum Spot Price Set? In the Middle Ages it hosted the largest and most important of the famous Champagne Fairs.

Merchants from across Europe gathered in the city to trade their wools, silks, leathers, furs, spices, and, of course, precious gold and silver wares. The Counts of Champagne, who prospered from this activity, introduced rules governing the efficient operation of the Fairs.

It is said that the system of measuring gold, silver and gemstones first used in their region took its name from the city of Troyes.

Troyes, ancient city in the Champagne region of France. Source: CC The troy system was in widespread use as the basis of several European monetary systems by the end of the 12th century.

Troy pounds and pennyweights fell from favour in the 19th century, but even when British legislation abolished other old weights and measures in , the troy ounce survived for trade in precious metals. As common as grain The troy ounce and the avoirdupois ounce have in common the grain, the smallest unit of mass in everyday use.

At grains, the troy ounce is heavier than the avoirdupois ounce, which weighs In metric terms, the troy ounce weighs The avoirdupois ounce is slightly less, at When referring to large quantities such as annual mine production , the industry often uses metric tonnes as the unit of measure as it produces smaller and more manageable numbers.