Ring without the right gem (5)
I believe the answer is:
pearl
'gem' is the definition.
(I know that pearl is a type of gem)
'ring without the right' is the wordplay.
'ring' becomes 'peal' (pealing is a kind of ringing).
'without' indicates putting letters inside ('without' can be similar in meaning to 'outside').
'the right' becomes 'r' (common abbreviation).
'peal' going around 'r' is 'PEARL'.
(Other definitions for pearl that I've seen before include "Gem; an attacked Harbor" , "See 12" , "Girl < , pretty" , "Small type" , "Object of great worth" .)