I found this today on a shipwreck beach on the Treasure Coast of FL. I posted in shipwrecks regarding this and a shipwreck item but any help identifying a time period would be great I believe it's the headrest to a chair??
It looks to be from a piece of furniture. I've seen those indentations (3rd picture)on old vanities and bureaus before. And the tenons appear to be from older furniture also. could be old naval/marine ship board furniture.