Oz vs Ozt: Differences, Similarities, Troy Ounces vs Ounces

Author: Focus on the User | 4 min read
Oz or Ozt

Although the name may confuse some, the troy ounce (ozt) is not the same as the imperial ounce (oz) that is more commonly used in the United States.

A troy ounce is equal to 31.103 grams. An imperial ounce is equal to 28.35 grams. A 1 oz gold bar must comprise more than 31.103 grams of gold.

Oz or Ozt?

Using an ounce instead of a troy ounce will result in a 10% error in your calculations of gold bullion prices. Quite a disparity in the gold business!

This can be perplexing because ounces are the standard unit of measurement in this field. Since an ounce is always a reference to a troy ounce when used in everyday conversation. To avoid confusion, know that the standard unit of measurement for gold and silver in commerce is the troy ounce.

Tory Ounces History

It has yet to be determined when or where the troy ounce system was first used, but its name appears to have been derived from the historic French trading center of Troyes. To facilitate trade with foreign merchants, it makes sense that they would have adopted a universal standard, given the global nature of the market at the time. This would allow for a universally accepted price for an ounce of gold. Interestingly, the Troy ounce may predate the French trading center of Troyes. Right now, one troy ounce is equivalent to one-twelfth of a troy pound. And one troy pound was precisely the weight of the bronze bars used by the Romans in the ancient Roman Empire.

The English first used the now-universal precious metals weight standards in the early 1400s after adopting them from the French. Almost three centuries later, in 1828, the United States of America officially adopted this norm.

How Many Grams in an Ounce of Gold?

Gold bullion is first and foremost measured in either troy ounces or grams worldwide.

There are 31.1034768 grams of pure gold in 1 troy ounce of .999 gold bullion.

It's worth noting that it's not uncommon for official and unofficial gold mint products to be slightly over-detailed, with an extra hundredth or two of gold.

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Identifying the Troy Ounce or Gold Gram Amount on Gold Bullion

Genuine gold bullion products will always have their exact troy ounce or gold gram weight clearly marked on them. The two most common gold bullion coins are 22-karat (The American Eagle coin is one).

This 22-karat gold American eagle coin has a purity of over .916 and is strengthened by the addition of silver and copper.

A simple calculation using the coin's weight of 33.95 grams and its purity of .916667 yields an estimated 31.12 grams of gold within this 22k Gold Eagle coin.

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Disclaimer: Content on this website is not intended to be used as financial advice. It is not to be used as a recommendation to buy, sell, or trade an asset that requires a licensed broker. Consult a financial advisor.

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