Criminal dealer acquires minute stone (7)
I believe the answer is:
emerald
'stone' is the definition.
(I've seen this before)
'criminal dealer acquires minute' is the wordplay.
'criminal' is an anagram indicator.
'acquires' indicates putting letters inside.
'minute' becomes 'm' (abbreviation).
'dealer' with letters rearranged gives 'eerald'.
'eerald' going around 'm' is 'EMERALD'.
(Other definitions for emerald that I've seen before include "Highly-valued variety of beryl" , "Small size of type, in printing" , "city in Oz?" , "La couleur" , "Green like this isle" .)