This is a clever trick with fairly cheap chips from Sam Dalal. What is particularly interesting from a historical perspective is the chips use the same methods that the great Danish Chip Master magician Per Clausen and others such as El Duco use to create some really wonderful effects. As far as I know Sam Dalal was the first to use this method, and although Per Clausen became famous for his brass chip effects there is no doubt they began with Sam Dalal.
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