(Jon of the Clue Crew delivers the clue as he weighs some metal on a scale) A French city lends its name to this system of weight used with precious metals, in which 12 ounces equals a pound
There are 12 troy ounces per troy pound, (373.24 g) rather than the 
16 ounces per pound (453.59 g) found in the more common avoirdupois system.