Hammerstone
A piece of stone, usually cobble size and often a cobble, with marks from impact from use as hammer....
A piece of stone, usually cobble size and often a cobble, with marks from impact from use as hammer....
A pebble or small cobble with a small circular depression in one or both faces. The depressions, if on both faces, are usually directly opposite. These items may be unfinished...
A piece of stone, usually cobble size and often a cobble, with marks from impact from use as hammer....
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A flake of stone struck from the core where the length is less than twice the width....