HELP! mystery brass with blue and white marble/cabision

[driftwood1963]

this was dug 9/2/13 at a site a friend and I have been working.
I was originally a 20 acre farm site [1870s]that was also used as a orphanage [1902-1912?] then later was a dormitory [1920-1927].
This was around 7 inches deep in the same area where we recovered several coins and horse tack.
the marble/cabision is set and don't move or roll but the brass top rotates on the base.

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[pippinwhitepaws]

well, this is a head scratcher for sure.

 

[gypsycarmen]

i say set it in the freezer for a bit see if the marble will shrink enough to pop out but I agree my Dad would pick up alot of things and pocket them as a kid he use to tell me his uncles would come to him he was the finder of all lost things