One question we hear from time to time is why coin shops, gold buyers, jewelers, and precious metal dealers often use pennyweight (dwt) instead of grams.
To someone outside the industry, pennyweight can sound like an old-fashioned or confusing measurement. Most people are familiar with grams, while very few use pennyweight in everyday life.
The reason is actually simple: precious metals are traded and priced using troy ounces, and pennyweight divides perfectly into a troy ounce.
Troy Ounces and Pennyweight Work Together
Gold, silver, platinum, and palladium are priced on the wholesale market by the troy ounce.
A troy ounce contains exactly 20 pennyweight.
That means if gold is trading at $4,000 per troy ounce, the math is easy. Each pennyweight is worth one-twentieth of the troy ounce value.
There are no odd conversions, strange decimal places, or rounding issues.
Everything works cleanly because both measurements belong to the same system.
Why Not Just Use Grams?
There’s nothing wrong with grams. In fact, many modern digital scales can display weights in grams, pennyweight, troy ounces, and several other units.
The problem is that grams do not divide evenly into a troy ounce.
One troy ounce equals approximately 31.103 grams.
That means every calculation requires additional conversion and rounding. The math still works, but it introduces extra decimal places and extra opportunities for confusion.
Using pennyweight allows dealers to move directly from weight to value without constantly converting back and forth.
Keeping the Math Simple
When we evaluate gold, silver, platinum, or other precious metals, we’re already working from troy-ounce market prices.
Using pennyweight keeps the calculations straightforward and helps avoid misunderstandings.
Once a transaction is complete, we’re happy to tell customers the weight in grams if they prefer. However, constantly switching between grams, pennyweight, troy ounces, and even pounds can actually make the process more confusing rather than less.
The important thing isn’t the unit being used. The important thing is that the weight is accurate and the calculation is transparent.
The Bottom Line
Most coin dealers, gold buyers, and jewelers use pennyweight because it works directly with the troy-ounce system used by precious metal markets worldwide.
It’s not about making things more complicated. It’s actually about making the math simpler, reducing conversion errors, and keeping everyone on the same page.
If you’d like to know your item’s weight in grams, pennyweight, or troy ounces, just ask. Any reputable precious metal dealer should be able to provide the weight in whichever unit you prefer.
Related: Learn more about how we test gold, understanding gold karats, gold and silver bullion, and how precious metal prices are determined.