Small craters, ranging in size from less than 1μm to about 1cm, on the exposed surfaces of lunar samples, caused by the hypervelocity impact of micrometeorites and dust particles with masses less than about 10-3 g; typical craters consist of a glass-lined pit, a ‘halo’ zone of fractured material surrounding and underlying the pit, and a spalled zone concentric to the pit. This spallation may leave the glass-lined pit standing on a pedestal.