Buddy’s ring cut from stone (3)
I believe the answer is:
pal
'buddy's' is the definition.
(both can mean a friend)
'ring cut from stone' is the wordplay.
'ring' becomes 'O' (letter resembling a ring).
'cut from' is a deletion indicator.
'stone' becomes 'opal' (gemstone).
'opal' with 'o' taken away is 'PAL'.
(Other definitions for pal that I've seen before include "Mate, buddy" , "Crony" , "Friend (colloq.)" , "Bud" , "China" .)