Break a slab, turning over about one ton of rock (8)
I believe the answer is:
basaltic
'break a slab turning over about one ton of rock' is the definition.
I can't judge whether this defines the answer.
'break a slab turning over about one ton' is the wordplay.
'break' is an anagram indicator.
'turning over' shows that the letters should be reversed in order.
'about one' becomes 'ci' (I've seen this in other clues).
'ton' becomes 't' (abbreviation).
'ci'+'t'='cit'
'cit' reversed gives 'tic'.
'a'+'slab'='aslab'
'aslab' with letters rearranged gives 'basal'.
'basal'+'tic'='BASALTIC'
Can you help me to learn more?
(Other definitions for basaltic that I've seen before include "Like igneous rock" , "Like black rock" .)