A corner fragment of a likely basalt basin, a stone vessel of which this fragment has a complete profile. The original instrument appears to have been very large and possibly quadrangular. The base looks like it was originally flat, and is 50% covered in white corrosion. The interior surface is covered in 80% white corrosion."Wall" thickness varies significantly between the "rim" and "base." The fracture surfaces are all hackley and 50% covered in white corrosion.
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