It's of rocky appearance (7)
I believe the answer is:
outcrop
'rocky appearance' is the definition.
'it's of' is the wordplay.
I cannot really understand how this works, but
'of' could be 'o' and 'o' is located in the answer.
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for outcrop that I've seen before include "Poor cut (anag.)" , "Rock formation at the earth's surface" , "Part of a rock formation above the surface" , "Rocks appearing at the surface" , "Jutting stone" .)