Troy Ounce Definition History and Conversion Table
One standard ounce, also known as an avordupois ounce, is used to weigh commodities like sugar and grain. It is slightly less than a troy ounce, which weighs 28.35 grams.
The troy ounce is the standard unit of measurement for purity in the precious metals market. It is often abbreviated as "t oz" or "oz t."
– The troy ounce is used to weigh precious metals.
– Equivalently, the troy ounce is 31.1034768 grams.
– A standard ounce weighs 28.349 grams, around 10% less.
– A troy pound (12 troy ounces) is lighter than a standard pound (14.6 troy ounces).
– The troy ounce is the only remaining metric in the troy weighting system.
The troy ounce is used to price metals like gold, platinum, and silver. When prices are listed per ounce, it is referring to the troy ounce.
Although the troy ounce was historically used for weighing gemstones, it has been largely replaced by the carat system.
Some historians believe the troy ounce originated in Roman times when 12 pieces called "uncia" or ounce, each weighing around 31.1 grams, were used to standardize the monetary system.
Before the adoption of the metric system, King Henry II adjusted the British coinage system to reflect the French troy system. Troy weights were first used in England in the 15th century.
Before the troy system, the British used the avoirdupois system to weigh both precious and non-precious metals. In 1527, the troy ounce became the standard measurement for gold and silver in Britain, followed by the U.S. in 1828.
In the U.S., the avoirdupois ounce is the standard for measuring food and other items, excluding precious metals and gems. It weighs 28.349 grams or 437.5 grains. The troy ounce is slightly heavier, weighing 31.1 grams or around 2.751 more than the avoirdupois ounce.
When the price of gold is quoted as US $653 per ounce, it refers to the troy ounce. There are 14.6 troy ounces in a pound, compared to 16 standard ounces. A troy pound consists of 12 troy ounces.
For quick conversion, refer to the table below.
Investing in precious metals is popular among those concerned with the difference between troy and avoirdupois ounces.
Gold, silver, platinum, and palladium are all valuable metals. Platinum is mainly used in jewelry and catalytic converters while palladium is found in equipment like medical and dental devices.
Modern investors have various ways to invest in precious metals, including commodity exchange-traded funds (ETFs) or mutual funds, stock shares of metal and mining companies, futures and options markets, and gold certificates.
A troy ounce weighs approximately 10% more than a standard ounce (1.0:1.097), and a troy pound is equal to 0.823 pounds.
To summarize, the troy ounce is the standard unit of measurement in the precious metals market. It is used to ensure purity standards and is referenced when prices are listed per ounce. Different from the avoirdupois ounce, the troy ounce is slightly heavier and has historical origins dating back to Roman times. It has been widely adopted in the British and U.S. systems of measurement. Investing in precious metals offers opportunities for both traditional and modern methods of investment.
