That appears to be a tie pin or a cravat pin, and it may have been quite common the fashionable look for its day, similar in popularity as his handlebar mustache, his haircut and his suit jacket were back then.
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To be fair, he most likely did not know that I was not yet alive, so he and I can pretty much call it a draw. Grrrrrrrrr.
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“Ken, I‘ll take Obscure Facts About Law Enforcement Officers for $200, please.”
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