Jewel box? (4)
I believe the answer is:
safe
'jewel box?' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for safe that I've seen before include "Cash-box" , "Place for keeping valuables" , "Uninjured, secure" , "Secure - place in the bank" , "Uninjured; excellent; lockable cabinet" .)