Featured Can you tell me anything about this brooch with glass button? vintage or antique?

Hello all! This brooch is a bit confusing. I tested it and it is holding at 18K but I'm not sure (maybe rolled gold? would be great if it was real!). It almost looks silvery under the gold when I look through a loupe. The central stone is glass and concave at the front. The back clasp looks hand made, unmarked. Do you think it's vintage, antique? Any info welcome, thanks!
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neat.....
that would be a lot of gold for a glass button........ but still neat !!!

with no marks...? artisan bench made ............

 

Fascinating piece!! In the second photo (at "nine o'clock") it almost looks like a maker's mark. Or is that something else?

 

Also wondered, maybe this was a special button. Like a button off an older relative's clothing, or possibly someone deceased. Maybe someone commissioned an artist to make a tribute brooch? (Especially if it is 18K)...

I think it is really cool what ever it is!

 

That's just an bit of a glare off the glass button in the second pic. I was wondering if the button was older

 

The pin is clearly somewhat modern, but wonder if anyone had thoughts on the age of the button?

 

There is a tiny bit of information on glass buttons with glass shanks on this page:
https://www.crazycrow.com/site/history-of-buttons/

Just once sentence, really, and it's vague: "Blown glass buttons with glass shanks appear in the 19th century and perhaps previously." This is about halfway down in the page linked above. And I just found the text above was copied from a 1994 research document written as a supervised undergraduate project, that is available online in pdf form.
https://trace.tennessee.edu/cgi/vie...article/1042/&path_info=Marcel_Sarah_1994.pdf

It appears that there is a lot of information about shanks in that document, but not much about glass shanks that were created as part of the button, not applied separately.

 

Thank you for sharing, great info!

 

I think of that tubular jewelry as dating to the 1940s.

Debora