Secret store of valuables (5)
I believe the answer is:
hoard
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">secret store of valuables</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 hoard that I've seen before include "Accumulation" , "Secret store of valuables" , "Accumulated store" , "Hidden stock" , "Rhoda (anag.)" .)