I too am unable to come up with a Vitro style name for it because it's a little off somehow.
For example, the Vitros I can think of that it looks closest to are All-Reds and Tiger Eyes, but I wouldn't call it either one of those.
I think they're actually Alox patches. The founder's granddaughter confidently describes how Mr. Frier tinkered around until he managed to get patches from his machines. She thought they were the big one-inchers. I think they are the ones in the tit-tat-toe games.
^^ well, MOST are slags in that compartment in the center. The blue one near the bottom of that compartment might be what we call a transparent swirl, a little later than most slags. And the marbles to the right are something else.
These are called slags. The companies would have called them "onyx" back when they were made in the early 1900's. But the collector name for them now is "slag".
That's how confused you had me. That Taz looked pretty old, but I knew it couldn't be before 1954. But that would still be a little old. You had my mind going every which way.
Interesting ... that you did it.
And that this 79-year-old man thought it was interesting enough to study and write an article about and encourage further study of.