I read somewhere that some opal white Pyrex was made without any identifying marks, so yours probably is Pyrex!
Sounds like the opal Pyrex to me also. Can you share a photo?
opal pyrex.....Hmm, yeah - give me a bit and I will post a pic.
You could bet your sweet bippi that it's a Pyrex. I'm sure you can find a pic in Pyrex love. They very rarely have a mark and were made for a very short time, like 1950-1952.People often pass them up because they lack pattern. Hope that helps
Hmmm I am thinking the first commenter is correct with the opal white Pyrex comment!
I have one similar to that as well and have wondered...
It looks Pyrex to me..or maybe Hocking