(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
...... the name "dollar" was used to refer to a unit of gold that 
had a weight of... [DOC] [TLE] Treatises and Essays on Subjects connected with Economic Policy ... [PAR] Expense of a Currency consisting of the Precious Metals.