When collected from a Riverton beach, stones are already rounded and smooth from hundreds of years of natural tumbling. When wet, the stones reveal their polishing potential – polishing brings out the colours more intensely and fixes their shine.
Below are photos of Riverton stones before going into the barrel with 100 size silicon carbide grit, the first stage of tumbling, and after four days in the of tumbling (they then go back for another three or four days to complete the first stage of the smoothing process):
