St. Louis Gold Buyers and Jewelry Center

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DWTs, Grams, & Troy Ozs - Jewelry

A diagram showing how to calculate troy oz grams and pennyweights

When it comes to weighing precious metals and gemstones, our jewelers often prefer to use pennyweights (dwt) instead of grams. It might seem a bit old-fashioned in our modern metric world, but there's a good reason behind it. See, one pennyweight is equal to 1.555 grams (or 1/20 a Troy Oz), which is kind of an awkward conversion. But jewelers like the dwt system because it's more precise for the smaller weights we typically deal with. And hey, "dwt" is quicker to say and write than "grams" too - when you're a busy jeweler, every little bit of efficiency helps! Plus, it's just tradition in the jewelry business. Jewelers' scales have been calibrated in dwt for ages, so why rock the boat? The dwt system is their trusty old friend. But we don't worry if a customer asks for the gram weight instead, converting is simple for our gem pros.


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