Thought it was a copper but found a cool piece of history, an 1860 campaign pendant for the the candidacy of John Breckenridge/Joseph Lane for president in 1860. Not much to look at, but clear enough to make out the names.
The middle was apparently a photo/likeness of each candidate made from some sort of iron compound, so it is totally toast.
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Here is an unabused look at what the pendant looked like back in the day.
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Also found a “heads I win” “tails you lose” coin. Its NC-17 rated; who knew these things existed (I didn’t)? I couldn’t find how far back these go, but given its toasted condition and that it was found near the 1860 pendant, it could be 150+ years old. The oldest I could find online was from the 1960s, but no way a coin that young would be this toasted.
Also found a sterling ring.