These are from a great aunt’s coat. She also had two black velvet large domed tops that were held to the pearl base the same way: by tying the ribbons through the holes. The velvet domes were worn threadbare. My mom said she wore the velvet for everyday and the mink for dressier occasions. In the second image, the pearl base is untied from the button at lower left to show the press-board part of the button construction.
The above is based on the National Button Society's Classification System.
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