Convert Ton (Assay) (UK) (AT (UK)) to Pennyweight (pwt) instantly.
About these units
Ton (Assay) (UK) (AT (UK))
The UK assay ton, slightly different from the US version, is defined as 32.666 grams. Like its American counterpart, it was designed so that milligram-level assay results could be easily interpreted as ounces of metal per ton of ore. In British mining operations of the 19th and early 20th centuries, the UK assay ton streamlined economic decision-making by directly correlating lab-scale measurements with bulk extraction expectations. Although now historical, its existence illustrates how different countries tailored their measurement systems to local mining economics and metal markets.
Pennyweight (pwt)
The pennyweight, equal to 1/20 of a troy ounce or 1.55517384 grams, is a unit used primarily in the precious metals and jewelry industries. Its origins lie in medieval English coinage, when the weight of silver pennies provided a practical standard for small masses. Jewelers continue to use the pennyweight because many traditional pricing structures and metalworking conventions are built around troy-based subdivisions. For gold, silver, and dental alloys, the pennyweight remains easier to work with than grams due to long-established norms. Even though the metric system is now dominant scientifically, the pennyweight persists because industries tied to history—especially those involving money and precious goods—tend to maintain deeply rooted practices.