Как по Английски будет тройская система мер и весов

noun

A system of weights used mainly for precious metals and gems, with a pound of 12 ounces or 5,760 grains.

Примеры использования:

Gold closed at $332.5 a troy ounce

proper noun

(in homeric legend) the city of king priam, besieged for ten years by the greeks during the trojan war. it was regarded as having been a purely legendary city until heinrich schliemann identified the mound of hissarlik on the north-east aegean coast of turkey as the site of troy. the city was apparently sacked and destroyed by fire in the mid 13th century bc, a period coinciding with the mycenaean civilization of greece.