People have always tried to standardize measurements and gold weight is no exception here. The problem was gold has been the universal money used all around the world, and there was different standards of weight depending on regions. However, globalization and modern standardization almost solved that problem.
There was a long history of humanity trying to standardize weight for trading purposes. However, it depended on the most influential empire at the past. Nowadays, it’s more like a worldwide agreement to use defined weights and their conversions to other weighting systems.
To make it easy among ourselves, we should try to convert different units of different systems to the standard metric system. In other words, we will convert all units to grams or kilograms.
Precious metals and gemstones weights were measured using the Troy system. It’s still the most popular system used for weighting gold and gems, with the Troy Ounce as the most popular weight of gold bars and gold bullion coins. Grains and pennyweights might still be common gold jewelry weightings in former British colonies and Britain. It is more common to hear these weights in the Western world more than in Asia.
- 1 stone = 14 pounds.
- 1 troy pound = 12 troy ounce.
- 1 troy ounce = 20 pennyweight.
- 1 pennyweight = 24 grain.
Note that 1 grain = 64.798 91 milligrams or approximately 0.648 grams, therefore the troy ounce = 31.1034768 grams and the pennyweight = 1.555 grams.
Other two popular weights in Asia are the Tola and Teal. The Tola is used mostly in India and its neighboring countries such as Pakistan and Nepal, while the Teal is generally used in Greater China and south-east Asia.
According to current standards, one Tola is 180 troy grains or 3/8 troy ounce, which is exactly 11.663 8038 grams. However, it was equivalent to 10 grams, and there are still some jewelers that use this old system. To avoid confusion, many jewelers in India sell gold in with 10 grams as a standard weight.
In Asia, especially in Japan and Greater China, jewelers weight and sell the gold in grams, with Kilogram as the standard weight of gold bars and the 500 gram bar as the most popular weight. The old Chinese system used Teal as the unit of measuring weights. The problem with teal is, it differs from a region to region and for the commodity itself! For instance, the teal in Hong Kong is approximately 37.7994 grams, 37.5 grams in Taiwan, 31.25 grams in China and a 100 gram in Vietnam! Confused enough? Silver teal was 40 grams, treasury teal is 37.5 grams and shipping teal was 36.7 grams while the rice teal is something else similar to the Vietnamese teal. In 1959, China standardized the Teal to be 50 grams to adapt the metric standard and ease this confusion a little. However, Hong Kong and Singapore still see the teal as 1 1/3 ounce, which is an approximately 37.7994 gram.