I have dug a watch chain of this type construction, along with the back of a pocketwatch pierced by a traingular bayonet, in a site near Harrison's Landing. This site has produced almost exclusively Civil war period Federal artifacts, and I am confident that this chain dates to the period. I have also seen such chains with nipple protectors dug in this area, although I don't have one in my collection. To see the watch chain, visit:
hope this is of interest.
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