I had started a file on these, I think they are moulds.. a cloth covered  
button,  and they are in  most cases military associated . There are  examples 
from a Philly site where a Rev war camp was located, shell waste of the  same 
type in the Caribbean area, Stan's sites etc.
 
We found a large amount at The James Anderson forge in Williamsburg,  
civilian but he also had contracts as the armorer during the Rev War. 
 
Ft Stanwix had buttons and a bit. If I remember correctly Caler and Bolton  
have buttons and bits in History Written with Pick and Shovel
 
Cannot find my ca. 1978 notes right now I think  Ft Michilimacinac may  have 
had some also.
 
Jim Parker
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