Looking at Don's link to the 1871 patents - Westlake had a "Zinc-board for stoves" March 21 1871 and then the "Platform for stoves" Oct 3 1871., which are the dates on the tag. I don't know if it came off a stove part but it does look to have come off of something. My first guess was a lantern - but now I'm looking at stoves
Anyway - here is another that was posted on Worthpoint. They didn't know what it was either but it sold for $30.24.
Interesting Chicago piece from the Great Fire period. 25mm in (?) bronze - thought at one time it might be an overstruck 2-cent piece but I don't believe it is. William Westlake was a railroad pioneer
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