Multi-color Glass Bowl

I found this glass bowl at an estate sale. The former owner was in her late eighties.
The bowl was covered in grime, nobody could tell what it looked like.
After cleaning it at home - the colors became eye catching.
It is a very heavy hand-blown multi-color glass bowl. It is 4" in diameter and 3.75" tall. The pontil is ground out.
There are a few air bubbles.
I have no other information. There is no signature or maker's mark.
I would like to find out as much as possible. Is it a spatter glass? What was the glass making process?
Thanks!