Girl of stone (5)
I believe the answer is:
beryl
This clue is a double definition.
'girl' is the first definition.
'stone' is the second definition.
(I've seen this before)
'of' is the link.
(Other definitions for beryl that I've seen before include "Gemstone of which emerald is a variety" , "Emerald or aquamarine" , "Mineral, aquamarine if blue" , "- - Bainbridge (lit.)" , "Green stone" .)