Steph

That white ribbon looks totally pelty to me ... but the rest of it ... well, it made me afraid to comment

Maybe 1940's

I think I'd keep it with the Pelts.

The seam is the main thing I was looking at. My main guess was MK but then I tried to think of who else might have that kind of color striation and so I thought maybe Vitro.

Not sure. My first two guesses would be Marble King or Vitro.

Left to right in top photo: #1. Maybe Master. The long seam in the first photo holds me back. In the second photo I think I might be seeing a hint of a shorter V-shaped seam. #2. I think I'm seeing enough of the seams to make a Peltier Rainbo call. #3. Probably Akro Cork. More views could nail it down. #4. This might also turn out to be an Akro cork.

Champion? Alley? Jabo?

Modern Asian ... AKA Imperial

Then I'll go with slag. I wish it was purple!

Peltier Multicolor Rainbo. A nice National Line era marble (early 1930's).

1 Vitro 2. West Virginia Swirl 3. I'd like to hear more about that one ... is that lighter color white? Because it's looking pink or purple on my monitor

Vacor Serpent -- has made many a person hope for it to be Peltier https://www.billes-en-tete.com/detail.php?id=51

Oooh, that's a keeper. Fascinating. A flat thing in the middle of looping vanes? I'd love to see how that is attached. I _guess_ it's a cat's eye. I _guess_ it's a Vitro. But ????

Forever!

Pepperoni, pineapple and horseradish pizza. Best food risk I've taken in a long time. Yum.

Oven brick is fun.

One vote for Vacor Rooster https://www.billes-en-tete.com/detail.php?id=49

1930's

Do you have a meat tenderizer hammer? The kind with lots of sharp points. I want to bash one with that! I'm still thinking ball mill ball, because of the weight, but I would want to keep trying to chip off that outer layer.

I like your weight comparison. That's interesting stuff.

Akro corkscrew 1930's.

Marbles like those started showing up with the Atlanta marbles (the stars and the magic marker marbles). I don't know what the origin story is for your marbles -- not the real story and not the story anyone told when selling them. The consensus has been that they're relatively new. It sort of looks like enamel to me. Any chance someone put an enamel finish on the industrial ball mill balls which were used to make the Atlanta marbles?

I was wondering about Bogard on the black cat that's almost front and center because it wasn't green-tinted. (Were there green tinted Bogards? You'd know better than I.)

How about a Vacor Wicked Owl? Not a great match to the main photo highlighted here, but some of the others have some closer marbles in them. https://www.billes-en-tete.com/detail.php?id=68