Dealer in gems (8)
I believe the answer is:
jeweller
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">dealer in gems</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for jeweller that I've seen before include "Maker of valuable adornments" , "Gem dealer" , "Shopkeeper" , "Dealer in gems" , "Setter" .)