Dust and rock on the beach? (6)
I believe the answer is:
ashore
'on the beach?' is the definition.
(I've seen this in another clue)
'dust and rock' is the wordplay.
'dust' becomes 'ash' (I've seen this before).
'and' says to put letters next to each other.
'rock' becomes 'ore' (ores are found in rocks).
'ash'+'ore'='ASHORE'
(Other definitions for ashore that I've seen before include "on terra firma" , "Beached" , "Aground" , "Hoarse (anag)" , "On land (as opposed to the sea)" .)