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Amgueddfa Cymru
Black and white photograph showing an early stage in the process at a coal cleaning plant.
This photograph shows a picking belt, on to which large coal falls, and by means of which it is conveyed along so that pieces of shale can be seen and picked out. On the left is the end of a conveyor that brings coal that has been washed, in order that it may be mixed with the large coal that has been picked over.
