Coober Pedy gem (4)
I believe the answer is:
opal
(Other definitions for opal that I've seen before include "item in Hatton Garden?" , "Mineral, usually iridescent" , "Type of gem" , "Variegated gemstone" , "Type of gemstone" .)
I believe the answer is:
opal
(Other definitions for opal that I've seen before include "item in Hatton Garden?" , "Mineral, usually iridescent" , "Type of gem" , "Variegated gemstone" , "Type of gemstone" .)