Mixture of metals (5)
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">mixture of metals</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 alloy that I've seen before include "Metal mixture" , "Mixed metal" , "Eg, pewter or brass" , "Eg brass or bronze" , "Mixture of two or more metals" .)