Glass antique cover like object -- ??

Another item from this recent estate with the perfumes, etc. It reminds me of something you would use to make your own paperweight like shadow box ...probably not using the right descriptors here, those little paperweight items with dried flowers, etc?

Thinking not a lid because it has magnification to it. The glass looks totally clear in the hand. 100% clear. But in these photos seems to have a blue tint, also if you hold up to white in the hand you can see a touch of blue, which also made me think older.

What did I buy for $2?

 

That's cool whatever it is.
I remember those make your own paperweights, from the 1960s. Often used with flowers.

 

I'm thinking it's likely one of these glass bubble magnifiers..

 

It could be a lid as well as a magnifier:

 

Thank you Komokwa and Moreotherstuff!