What is a Troy Ounce?


May 3, 2020

There are many types of currency in the world, but the most consistent, reliable, and dependable are precious metals like gold and silver. And the most accurate way to measure these metals–a system that has long become a standard–is by troy ounces. Beginning in the middle ages, the history of the troy ounce is a long and interesting one. From its beginnings in Troyes, France, this unit of weight measurement became a standard across the world for some of the most precious elements on earth. The weight of the troy ounce is 31.1034768 grams, as according to the U.K royal mint and commonly referred to as t oz or oz t.

But, let’s get to the crux of the matter: what exactly is a troy ounce?

Why “Troy Ounce”?

Two theories surround the origin of the word, the first being when English traders took their goods to Troyes, France, and exchanged items with the locals. It is thought originally to have been a familiar term for the locals to understand, a platter being described as 1 troy in the Earl of Derby’s 1390 travel journal. Adding to the mystery, another theory suggests statues from the time of Henry III or Edward I were engraved with troni ponderacionem meaning ‘troy weight’ with troni meaning market, overruling the previous theory in many ways as this is backed with facts dating back to 15th century England.

As trade in Europe flourished, a new standardized monetary system was needed. After years of searching, traders finally settled the troy ounce system, urging every corner of Europe to adopt it, even boasting it was based on an ancient Roman system (whether such a claim was true or not). In the end the troy ounce became a standard system for the measurement of monetary metals.

According to JM Bullion, a precious metals company, England did not need much convincing as the King of England, Henry II styled the English system of the time upon that of the french troy named avoirdupois system, meaning ‘goods of weight’, around the 1300s.

It wasn’t until around 1400, however, when the system we know today became established–its “crowning” moment taking place when the infamous and ruthless King Henry VIII adopted the coinage of gold and silver on a strict troy ounce basis in the year 1527.

By this time many other countries around Europe were also using their own independent version of the Troyes system. Take, for instance, the Paris troy and Holland troy. By 1824 Britain had created the British imperial system of weights and measures, which was more or less an official name for the troy system that had already been in use for hundreds of years prior. This system remains up to this day as one of the standard methods for weighing gold and silver.

Although it is widely accepted that the troy weighting system originated from Troyes, France, other countries developed similar systems. For instance, the state of Bremen in today’s Germany was known to have a weight system almost identical to the troy weight system.

Medieval England is not the only stage in the long and fascinating history of this metal weight. Interestingly, similar systems were also in use around the world from the beginning of time. For example, there has even been suggested evidence of a far more simple yet effective method being used in the bronze age where measurement would be based upon a single seed or a grain. This system is likely the origin of the term a ‘grain’ used today. This system is also thought to have brought about problems due to the fact that some seeds and grains are heavier than others but it was a system that was widely recognized between all languages and cultures just like it is today.

In a slightly more controversial alternative origin of the modern system, it has been suggested it came from Muslim domains by the way of trade routes. In this alternative version, traders who frequented these routes helped spread the use of these measurements long before they were adopted in Europe. The currency it is thought to have been inspired by is the dirham, deriving from the ancient Greek drachma, which is an ancient currency used by the Persian and Ottoman empires as well as many African countries to this day, proving its reliability and consistency.

Unlike Bitcoin and other cryptocurrencies, gold is typically much more stable.

This theory about dirham is also supported by the way the troy system is tied to early Anglo-Saxon England and its evolution toward the British coinage today. The link begins when the Anglo Saxon king Offa of Mercia began a currency reform at around 770AD which saw the then-used currency replaced with another coin, the silver penny. This new coin is thought to have been derived from the dirham (based on similarities that both displayed).

From that point on, the monetary system in England was shaped for centuries to come, based on silver penny, its weight set at twelve pence for a shilling, twenty pence for an ounce, and a pound at twelve ounces or twenty shillings. This system is based on the dirham, a style molded by Roman and Charlemagnian influence, both holding superior cultural and economic technologies at that time.

Over the years, wars, famines, and general economic depressions occurred. In response, kings debased the coins in weight and finesse making the system much more unstable and uneven. This means measurements became less precise, the maths would have become very hard, leading to arguments between citizens, traders, and nobles alike. Over time, the weighting system was slowly replaced by the troy ounce that we know today.

Benefits of the Troy Ounce

The standard ounce used today is not as widespread as this previously mentioned system and can only be found in the US and Britain. Despite the fact the French do not employ this scale, we still use the original Middle Ages name for it, avoirdupois ounce in full but commonly it is known as simply an “ounce.” These avoirdupois ounces measure sugar, chocolate, salt, anything but precious metals, precious metals are entrusted to the troy ounce. Maybe people are left with the question of why? Why do they get their own special system?

The answer to this lies in the advantages. The advantages of having these two separate systems are that it easily avoids confusion and makes sure everything is clear to the customer when purchasing these precious metals. For example, they might be a Swiss national buying from an American national who has all his prices per weight in standard ounces as is the norm in America. However, it’s not the norm for Switzerland so it is essential to have a level playing field so both parties feel they are being treated fairly and do not have an advantage over one another. This is what many refer to as the intercontinental reach, where everybody speaks the common language of these precious metals.

It’s also essential they are kept separate and away from all other aspects of life as one of the prime focal points of these metals is security for banks and individuals in case of market crashes and other disasters. Thus this measurement must be in its own neutral league because something so simple as the way it is measured is just as important as being hidden underground, under lock and key. The troy ounce is an ancient and well-respected tradition, just like the trade of precious metals, meaning keeping the same system that was used all those centuries ago allows metals, older than any trading market and any currency in the world today, to keep their consistency and ensure their purity.

This is essential as precious metals are a fail-safe so banks and ordinary people won’t lose everything they have during market crashes and recessions. Currencies crash, change, and inflate, but gold, silver, platinum, and palladium do not. They can be relied upon and entrusted throughout time.

In comparison, the troy ounce is slightly heavier than your average ounce, about 10% heavier to be precise. A normal ounce weighs in at 28 grams, and a troy ounce weighs in at 31 grams, per ounce. A kg of troy ounces would measure in at 32 T oz; there are 12 troy ounces in 1 troy pound. It is important to remember when looking at the price per ounce of gold that it is talking about troy ounces and not standard, avoirdupois ounces. It is important to know this information as some sellers online will list their prices in the standard ounce to try and trick customers so it is essential to check and double-check just to be sure you are not losing out.

If you ever spy a website that does not have it listed in troy ounces, multiplying the regular ounce by 0.91 will give you its weight and worth in troy ounces. Here at GSI exchange we always list our prices in troy ounces. Furthermore, when making up a troy pound it’s important to remember that despite the fact that a troy ounce weighs more than a regular ounce a troy pound weighs less due to the fact it takes fewer ounces to make up the pound, it is important to take this into account when buying, selling or trading precious metals to make sure you get the best deal possible. Bullion is a word that will appear often when browsing metal sites and used every day in the trading industry; it simply means the trade of metals in bulk before coining or valued in weight.

Similar to the standard ounce, if one of your precious metals weighs less than 1 troy ounce you would use grams and then milligrams and then micrograms going all the way to nanograms. Meaning ounces and troy ounces have the same beginnings but take different paths when in larger amounts. However there is an alternative break-down scale you can use for precious metals, one used just as often as the latter, so it is important to familiarise yourself with the two. The scale I am talking about is the traditional old-style scale starting at a troy pound then a troy ounce leading on to the pennyweight and ending at the grain.

Now you may be left with more questions than you started with like “what is a grain,” or “what is a pennyweight?”. These are units of measure that are often used in the industry.

First, let’s talk about grain, this unit is equal to 64 milligrams and is commonly used in the prospecting and mining side of business as deposits are so small they can be measured in this way. It can also be used in helping to exactly measure the other mentioned unit known as a pennyweight which derives its name from the fact it used to be in Anglo-Saxon times the weight of a penny, it is also often shortened to DWT with the D bearing the history of ancient Rome as it stands for a denarius, a Roman coin that was roughly equal to the penny.

Inside a DWT there lie 24 grains, then 20 DWT inside of one troy ounce and 12 troy ounces in one troy pound. The reason this came about is due to the fact English currency in Anglo-Saxon times would have been 240 pennies to the pound and the British monetary system worked by setting itself around the tower pound which was equal to this and it was so reliable and consistent it remains in place today.

Yet another form of old English measurement that is still in use today is mint weights which can also be referred to as moneyers weights. These small but precise units of measure were legalized by the British parliament on 17th July 1649 and the bill was aptly named An Act Touching the Monies and Coins of England. These weights were used in the exclusive business of minting coins to an exact standard making sure everything is fair and equal in these very royal and noble businesses.

Unlike the global market, these weights were used in coin minting and not trading. Buying or selling large quantities to pounds and ounces were not necessary; they worked on a much lighter system of scale close to the milligram end of things. Beginning with something familiar, a grain comes first which in turn is equal to 20 mites, a mite being equal to 24 droits, a droit being balanced with 20 perits and finally, a perit corresponds to 24 blanks.

When it comes to the reliability of an investment, precious metals are king.

Other Foreign Systems

Scotland had a slightly different way of doing things compared to its southern cousin: they used a system which involved terms like drop and stone, which multiplied by 16, or specifically, 16 drops to the troy ounce and 16 ounces to the troy pound and 16 pounds to the stone. This was not the only method they employed for the measuring of precious metals, stones, and gems, but it was the most widely used and best understood by its foreign traders.

During the time of an independent Scotland, most of the country’s trade deals came with England, who valued the Scottish pound to 7716 English grain which was 716 grains heavier than an English pound. Therefore after the Union of England and Scotland, the British government decided to round the Scottish pound down to 7680 grains meaning it could be easily traded without difficult maths as it made the ounce and grain equal to the English standard.

The Dutch had a particular way of doing things also, and they based their system upon a mark of 8 ounces, the ounce of 20 engels, which were equal to 20 pennyweights, and the Engel of 32 As. The mark was rated at 3798 grains, this being identical to the tower pound system, suggesting it was of similar or not the same origins. One country that has refused to adopt troy ounces all together, not just in the past but the present and foreseeable future as well, is China. The People’s Bank of China prefers to use an international system of weights or SI weights to issue and mint their ‘gold pandas’.

Final Verdict:

As we can see, there is a long and complex history surrounding the troy weight system. But from it’s complex past, we can track the reliability of investment in it in the current day. Throughout the rise and falls of all currencies the world has seen, including the metric system, there has been one clear winner, precious metals and the people who invest and hold on to them. With impending disaster scenarios, like widespread warfare and unrest, the collapse of national and central banks, pandemics, and predicted looming market crashes, people around the world are wising up. Just like through the long complex history of the troy ounce, where other currencies falter, gold is king. From answering the question what is a troy ounce, we find yet another reason to invest in gold.