Perhaps I turned to stone (8)
I believe the answer is:
sapphire
'to stone' is the definition.
(I've seen this before)
'perhaps i turned' is the wordplay.
'turned' indicates an anagram.
'perhaps'+'i'='perhapsi'
'perhapsi' is an anagram of 'SAPPHIRE'.
(Other definitions for sapphire that I've seen before include "His paper can be turned into a jewel" , "Deep blue colour" , "sparkler" , "precious item" , "His paper can be made into a jewel" .)