Ripping bits of granite (7)
'ripping bits' is the definition.
'tearing' can be an answer for 'ripping' (I've seen this before). I'm not certain of the 'bits' bit.
'of granite' is the wordplay.
'of' indicates anagramming the letters (the answer comes from or \'of\' the letters).
'granite' anagrammed gives 'TEARING'.
Can you help me to learn more?
(Other definitions for tearing that I've seen before include "splitting", "violent", "Granite (anag.)", "'Pulling apart, ripping (7)'".)