A small sledge—for example a 2 or 3-1b head on a 14-in.
handle—may be needed to collect fresh samples of especially tough rocks.
All hammers are potentially dangerous, because heavy blows may send off
rock spalls or steel flakes at high speeds. It is truly important, therefore:
(1) to wear safety goggles (which fit over glasses); (2) not to strike heavy
blows when people are nearby; (3) never to strike one hammerhead with
another, as when using one as a wedge; and (4) to strike angular rock edges
so that spalls will fly to the side rather than toward oneself (Fig. BIA). The
hammerhead is less likely to spall if the corners and edges of the striking
face are filed or ground to a bevel.