My Gold News | 21 February 2023

What is a Troy Ounce

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The term, “troy ounce” is used quite often in the context of precious metals. A troy ounce is best defined as a measurement unit that determines the weight of a precious metal like gold and silver. This unit of measurement has been used by humans ever since the days of Ancient Rome.

Troy Ounce History

The name of “troy” is thought to have been first used way back in the late 14th century. Some link the word “troy” to a popular fair held in France's city of Troyes. It is unclear as to whether this connection is legitimate. Some historians argue that the story linking the word “troy” to Troyes' fair was made up in the 18th century. The fact that the troy ounce is a component of the troy weights system is not contested. Numerous aspects of the troy weights system have their roots in the ancient Roman system of money. Romans made use of bronze bars of various weights for currency. Heavy bronze, referred to as “aes grave” weighed a single pound. The ancient Romans referred to one-twelfth of heavy bronze as an “uncia”. This is translated to “ounce” in English. As time progressed, the imperial ounce became standardized as one-sixteenth of a pound. However, the troy ounce is one-twelfth of a troy pound. At one point in history, the troy ounce was utilized as a component of the apothecaries' system. It was used in medicine for years until eventually being replaced with the metric system. The troy ounce was also used in Britain as the British Imperial troy ounce. The imperial troy ounce was nearly identical to the troy ounce of Britain used in the 18th and 19th centuries. The English declared the troy ounce as official coinage in 1527. Yet most historians estimate that troy ounces were used in the country since 1400. 


The Difference Between Troy Ounces and Regular Ounces

Do not confuse troy ounces for regular ounces. A traditional ounce is also known as an imperial ounce. An imperial ounce weighs 26.5 grams while a troy ounce weighs 31.103 grams. If one were to hold 31 pennies or compact discs, the weight would be equal to that of a troy ounce as each penny/compact disc weighs a single gram. All in all, a single troy ounce is 480 grains, making it about 10 percent heavier than an imperial ounce that weighs 437.5 grains or 28.3495 g.

The Utility of the Troy Ounce

Bullion prices are typically quoted in troy ounces due to the fact that it is the weight standard of the US Coinage Act of Congress passed in 1828. The exception to this standard is found in East Asia. As an example, the People's Bank of China does not use troy measurements. A troy ounce of gold is identified with a currency code of ISO 4217 XAU. A single troy ounce of silver has the denotation of XAG. It is worth noting that the vast majority of jewellery weighs under an ounce. This comparably low weight is why the price of jewellery is quoted in grams.

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If you are looking for gold, silver, or other precious metals, MyGold is at your service. We have gold and silver bullion and coins along with other precious metals for sale at reasonable prices. We are also interested in buying your coins and bullion. Reach out to us at 0800 465 369 to learn more about our precious metal selection.