Dust and mineral aggregate 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 mineral aggregate' is the wordplay.
'dust' becomes 'ash' (I've seen this before).
'and' is a charade indicator (letters next to each other).
'mineral aggregate' becomes 'ore' (I've seen this before).
'ash'+'ore'='ASHORE'
(Other definitions for ashore that I've seen before include "Hoarse (anag)" , "in port?" , "Going on land from sea" , "Off the boat" , "On land (as opposed to the sea)" .)