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What Are Troy Weights? Unit Conversion—The Math You Need
Troy (t) refers to an old British system of weights You can learn more about unit conver-
(masses) that is now used globally to quote the weights sion (including problems on converting
of precious metals (gold and silver) and gems. It is weights) at this site featuring The Math You
based on a 31.1-gram troy ounce (ozt) and a 12-troy- Need, When You Need It math tutorials for
ounce troy pound (lbt). Because some gems and jewelry students in introductory geoscience courses:
pieces are small, jewelers often express their weight in http://serc.carleton.edu/mathyouneed/
troy “pennyweight” (abbreviated “DWT”). One penny- units/index.html
weight is equal to 1/20th of a troy ounce (0.05 ozt) or
1.555 grams.
Looking for additional review and lab prep materials? Go to
www.masteringgeology.com for Pre-Lab Videos, Geoscience
Animations, RSS Feeds, Key Term Study Tools, The Math You Need, an
optional Pearson eText and more.
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