This is a very large 1 & 3/4" brass button, probably from the late 19th c. or just a little later, from Germany, embellished with a relatively massive pressed glass bust of Achilles in sepia-tinted milk white glass. (I have only seen this type of button now with Achilles and Tutankhamen.) The only defect is a spot of soft solder on the back where someone had attached a loop, but I am sure this one was always a button, and not a clasp. It's in very fine condition.
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