Figure 4
From: Stone axes throw new light on Baltic stone age mortuary rites
(a) Experimental polished stone surface used for grinding ochre and lard on rawhide supported by wood, (b) Macro traces after 30 min of back and forth rubbing activity, scale bar equal to 2 mm, (c) Micro traces after 60 min of back and forth rubbing activity, scale bar equal to 100 μm.
