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Precious Metal Weights
Definitions & Conversion Charts

There are 3 methods for measuring weight:

1. Avoirdupois is the system used for business/commerce and the most common. We've all seen the 5 lb. bag of potatoes.

2. Apothecaries is the system used by pharmacists (medicines).

3. Troy is the traditional system used for measuring precious metals such as gold, silver, platinum and the one we will be looking into on this page.


   12 Troy ounces = 1 Troy pound
   1 troy ounce = 480 grains
   1 troy ounce = 20 pennyweights (dwt)
   1 troy ounce = 1.097 ordinary (Avoirdupois) ounce
   1 troy ounce = 31.1034768 grams
   14.583 troy ounces = 1 ordinary (Avoirdupois) pound
   32.15 troy ounces = 1 kilogramme

   1 pennyweight = 24 grams
   1.55 grams = 1 pennyweight
   20 pennyweight = 1 troy ounce
   240 pennyweight = 1 troy pound
   24 grains = 1 pennyweight
   1 pennyweight = .05 troy ounce
   1 gram = .643 pennyweight

   1 gram = .03215 troy ounce
   1 gram = .643 pennyweight
   1.55 grams = 1 pennyweight

 Standard (Avordupois) ounce to Troy ounce multiply by .91
 Standard (Avordupois) ounces to pennyweight multiply by 18.2
 Standard (Avordupois) ounces to grams multiply by 28.35
 Troy ounces to pennyweight multiply by 20
 Troy ounces to pounds troy, divide by 12
 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

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If you've been thinking about collecting or investing in gold, visit to see current gold values, gold information and excellent buys.

FREE Online Tools for Calculating Ounces to Grams AND $$$ Value of Gold Jewelry

For more information on gold and how to figure the gold content of your gold jewelry (14K, 18K) visit 'Gold'.

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