Ancient Ilium (4)
I believe the answer is:
troy
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">ancient ilium</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for troy that I've seen before include "City of Paris" , "System of weights for measuring precious metals and gemstones" , "City besieged by the Greeks - system of weights for gems" , "Ancient city of the Iliad" , "Precious stone weight system" .)