✅ SOLVED Mysterious glass topped object found in close proximity to school yard

[OhioTrevor]

Was back at an old turn of the century school house and found this thing. Any ideas what it might be? The top is made of glass. If you remove the round glass object, it is in a hollow bowl.

 

[desertexplorer]

Your find if an old glass sign reflector. They came in a number of different porcelain signs from the 1930’s through to the 1960’s. including stop and railroad signs.
You can search ebay for “glass reflectors signs” and you’ll come up with hundreds. The common sizes were 5/8” and 3/4”.

 

[OhioTrevor]

Thank you desertexplorer! You solved it.