Silver, in heraldry (6)
I believe the answer is:
argent
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">silver in heraldry</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 argent that I've seen before include "Silver on a coat of arms" , "(In heraldry) silver - garnet (anag)" , "White" , "Heraldic term for silver" , "Colour" .)