The most common mistake people make when buying or selling precious metals and coins, and how it can cost you.

At least once a week at the refinery we come across someone who is unfamiliar with weighing gold or silver. We explain weights to them, and they understand, but there are unscrupulous people out there who do not explain and take full advantage of the confusion.

If you are planning on purchasing coins, precious metals or sending scrap jewelry in for refining there are a few very important things you need to know.

It is surprising to some, but there are totally different methods for calculating weight for silver and gold (and even gun powder) than used to calculate anything else.

When you buy or sell precious metals, the weight can be measured in a variety of ways. It is important that you are comparing apples to apples, particularly when buying coins and bars over the internet. This is not as important if you are buying just a few ounces of silver but the discrepancies can certainly add up fast.

The international standard measurement for Gold and Silver is in Troy Ounces. 1 troy ounce = 0.91 ounces (standard US ounce or Avoirdupois).

When you buy a 100 ounce gold bar, it is actually 109.714 standard ounces or Avoirdupois ounces and it doesn’t weigh the same as 100 ounces of sugar for example.

1 troy ounce (t oz) is 2.75 grams heavier than a standard ounce. When you send in refining materials or buy or sell gold or silver, it is crucial you make sure when you weigh your scrap/item on a standard jeweler’s scale or food scale, that you convert the ounces to troy ounces. See the conversion table below.

Multiply the number of Ounces (Avordupois) by .91 to get the number of troy ounces.


Gold & Silver are such universal and important materials that a “standard around the world” measurement system is required, it is not an option.  This standard is called the troy ounce. Here at Pease & Curren we only measure in troy ounces, we give all results in troy ounces. If you send in scrap and standard ounces are marked on your paperwork for instance if you weighed your scrap on a bathroom scale or food scale, we convert it immediately to troy so we are all working off the same measurement.


Gold and silver are measured in Troy weight, a system that includes pennyweights, ounces and pounds. The ounces and pounds do not equal the Avordupois or customary U.S. system that other common goods are measured in. For example a troy ounce weighs about 10 percent more than an Avordupois ounce.

  • 24 grains = 1 pennyweight = 1.5552 grams
  • 1 gram = .64 pennyweight
  • 1 pennyweight = 1.56 grams or .05 troy ounce
  • 20 pennyweight = 1 troy ounce = 31.1035 grams


  • Avordupois Ounces to Troy ounces multiply by .91
  • Avordupois Ounces to pennyweight multiply by 18.2
  • Avordupois ounces to grams multiply by 28.35
  • Troy ounces to grams multiply by 31.1
  • Troy ounces to pennyweight multiply by 20
  • Pennyweight to grams multiply by 1.56
  • Pennyweight to troy ounces multiply by .05 (or divide by 20)
  • Grams to pennyweight multiply by .64
  • Grams to troy ounces multiply by .032
  • Grams to carats multiply by 5
  • Carats to grams multiply by .2 (or divide by 5)
  • Carats to “Points” multiply by 100
  • “Points” to carats multiply by .01 (or divide by 100)


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Do you have scrap jewelry, bench sweeps or jewelry that you need to extract stones from? Get free containers, shipping and insurance below. If you are still unsure about measurement, Chat with us on our website or call in at 800-343-0906 and we’ll help you out.

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