I'm no expert, but this form, in general, can be found from the early to the later 19th-century.
If it has hallmarks they will look like tiny stamps of shapes/letters/numbers. Hallmarks are found on English and European examples, but rarely on American examples.
These were made by a lot of different companies. Unless a stamp or other mark is found we may never know exactly who made it. I'm pretty sure Ezra C. Dean was the owner who had their name engraved on it.
Most of these were either gold-fill or gold plated. This one is probably gold fill, which means a fairly low-level of gold, but is more reliably gold-looking than plate, which can rub off.
It's a nice example of one, and most likely earlier in the 19th-century rather than later, so could possibly be civil-war era. And BTW, a nice example from the 1880's is really no more valuable than a similar one from the 1860's.
I'm definitely not an expert in value, but I'm curious what you paid?
Mind if I share the pictures with an outside forum with experts who will know something more than I do?
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