Intermediate Quiz: What caused these marks? 0

[Insider]

This is a continuation of an old quiz where my statement that the incuse marks on a coin resulted from sawdust.  At one time WOOD DUST was used to dry Morgan dollar planchets.   Most cleaning or circulation tends to cause the debris to fall off.  If you search, eventually you will be able to find some of these particles still attached to a struck coin as on this 1886 dollar.  The dust comes in all sizes from pin-point size to the largest chunk I've seen about 1/16 x 1/4 inch!  Very often fiber lines can be seen in the depression when the wood is removed.   The color is adjusted to show the brown color of the debris.  

[Henri Charriere]

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