Worth its Weight in Gold

Gold has its own set of measurements in regards to weight that should be fully understood before you engage in any gold buying or indeed gold selling. The system of measurement of gold weight is known as the Troy system. This is a universal system and when you see the advertised gold price anywhere in the world it is the price of one troy ounce which is different from a normal ounce that we would talk about in other aspects of life such as baking. The Troy system is specifically for gold and silver and has been used historically across the globe. It is said to take its name from the city of Troyes in France. It is the official system of measurement as adopted by national mints across the world.

The more common system of measuring weight is the avoirdupois system in which there are 16 ounces to each pound of weight. The Troy system is different in that within each Troy pound there are only 12 ounces as opposed to 16. The metric system using Kilograms and grams has also been incorporated in the discussion of gold weights with the Troy pound being a redundant term. Often larger gold bars are described in terms of how many grams or kilos they are. The metric system remains a constant unit of weight when talking either about the avoirdupois or the Troy system of measurement. It is indeed perhaps one of the easiest ways to explain the difference between the two systems.

In order to understand the Troy system it is perhaps best to think of it in terms of the avoirdupois system with which everyone is much more familiar. Therefore, converting between the two systems may make it easier to understand gold weights especially if you are interested in buying either gold bars or gold coins, or alternatively selling small pieces of jewelry and therefore wanting to know what value you can expect from them.

The Troy Pound

A troy pound has 12 ounces within it and weighs 373.24 grams. It is the equivalent of .82 of an avoirdupois pound.

The Troy Ounce

There are 12 Troy ounces in a Troy pound. Each Troy ounce is the equivalent of 31.1034768 grams. This makes the troy ounce heavier than the avoirdupois ounce, which is only 28.35 grams. One Troy ounce is in fact the equivalent of 1.09714 avoirdupois ounces therefore making it almost 10% larger than the latter. If you are purchasing a one ounce gold coin it is important to know that this is a troy ounce and therefore the weight of the gold coin will be 31.1034768. If you are selling gold and you make a mistake between the avoirdupois ounce and the Troy ounce this could end up being a costly mistake. After all, if you sell a troy ounce for the price of an avoirdupois ounce in the current market you could end up $200 out of pocket. Consider then if you are selling 12 ounces the mistake that could be made.

A troy ounce is then further subdivided into pennyweights which are again further subdivided into grains, the smallest unit of measurement within the Troy system.

The Troy Pennyweight

A troy ounce is then further divided into pennyweights (dwt). There are 20 pennyweights to the troy ounce which means that there are 240 pennyweights to the Troy pound.

The Troy Grain

The pennyweights are then further subdivided again into the very basic unit used to measure gold -- that of the grain. There are 24 grains within a pennyweight which means that there are 480 grains within a troy ounce.

This amount may seem miniscule; however, when we consider that often gold is mined as a dust it starts to become clear that there is a need for an extremely small unit of measurement to take this fact into account. At a very basic mining level people may mine only a few small grains of gold dust at a time.

Converting Avoirdupois to the Troy System

A quick and simple formula to convert the avoirdupois weight to the Troy system is to simply measure the no. of avoirdupois ounces by .912. The result will give you their approximate weight in troy ounces.

Converting Grams to the Troy System

Here are some formulas which will make it easier for you to convert an amount in grams into an amount within the Troy system.

Formula for converting grams to pennyweight
No. of grams x 0.6006006 = dwt

Formula for converting grams to Troy Ounces
No. of grams x 0.03003 = troy ounces

Therefore a quick review of the measurements within the Troy system is:
One Troy lb = 12 Troy ounces
One troy oz = 480 grains
One troy oz = 20 pennyweight (dwt)
One pennyweight = 24 grains
One troy oz = 31.1 grams

It is a good idea to understand exactly what each weight refers to if you are interested in either investing in gold, buying gold jewelry or beginning to collect gold sovereigns. If you are in doubt at all about the measurements many gold based websites also contain a calculator and conversion tool so that you can work out exactly what weight of gold you are dealing with.

Gold coins come in standard sizes within the Troy system. A sovereign coin is .2354 troy ounces or alternatively 7.9881 grams. A Kruggerand is a one ounce gold bullion coin. This is a troy ounce and therefore it weighs 31.1 grams.

Gold bars on the other hand can come in a wide variety of sizes. The most traded gold bar is the kilogram gold bar which is 30.03 troy ounces and 2.5025 Troy pounds. The largest gold bar currently cast is 250 kilograms and is owned by Mitsubishi in Japan. In troy pounds this would be 7507.5 troy ounces which considering the current price of gold is over $1800 means it is worth a substantial amount of money and its value has more than doubled in the last couple of years.

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