I would call this one a white on black "Prize name".
True black is a hard thing to find in the world of glass.
There are a few recipes out there but most of the black that you will see in any glass is either purple, brown, green or blue--I may have forgotton a color here.
I finished doing a partial backfill on a "Prize name" box a few years back.
It took up a lot of time but it was all too fun and enjoyable to call work.
The white on black was the hardest to find for me and I only needed a few.
Nice find.
Marble--On!!