Alan

I'm not a Vitro person, but it says Vitro to me.

Not bricks, no oxblood. Game marbles, absent indications otherwise.

Post a few well-focused pics with no more than a dozen marbles in each. We can start you from there.

Given I have seen some others that are essentially the same, the green was likely expected. But as I like to say - almost anything can come out of a marble machine. Note that my example was from the Akro site French Drain oxbloods cache, dug by "W". Almost all marbles from that site location were odd in some way.

Because I'm wondering whether it is similar to this (which I can accurately ID the source):

The best answer is to watch the processes and study the result. Tank work involves the construction of a cane, one layer and one step at a time. Sometimes the step is a twist or a cane/frit pick-up or pulling the cane down. The slower approach is to study and understand how a cane construction marble is made by looking at photos, perhaps Youtube videos. There are a number of types - just as in vintage handmades. Each has it's own approach to the process, but the basics are the same. Over time you can look at a piece and reverse-engineer how it was made step-by-step. The torch/cane difference is easy to pick up with some study. They are quite different. ETA: The VERY best is to to take classes at studios. I took torch lessons from Kate Fowle which were 90% bead making, but the process for handling glass at the torch is similar. I have tank experience at Wheaton and a glass studio conveniently 15 minutes from me. Both helped immeasurably - not to mention watching true professionals like Ro Purser, Geoff Beetem, Mark Matthews, Harry Besett, Josh Simpson etc. Harry Besett:

Torch: Tank (Geoff Beetem):

I'd have to see it without the backlight effect.

I'm not familiar with him so I looked him up. All of the examples of his work is torch work. The OP piece is a tank piece.

Those in the posted link are common.

The construction is fairly unremarkable. What is odd about it is that most artists wouldn't use a dark core like that. It kind of disappears. The "I" appears to be someone's signature, but not one I am familiar with.

All common. Perhaps you can share specifically which ones you see as rare, and why.

Not "electric" orange in the commonly accepted use of the word in the collecting hobby.

Thanks. Given the math, I suppose that means "yes". I just checked the truck and its just labeled 'Marble King, Paden City'.

Remind me: Is the Marble King truck a 50th anniversary item?

None of those are Akro, for me.

If I can suggest something (for Birdy as well): You might start a thread looking for other collectors within x hours drive from some relatively popular locale. Take an inventory and then consider creating an impromptu marble meeting. It can be done practically anywhere. Years ago we had a very small local group that met after hours in a comic book store run by one of the collectors. It was relaxed, slow and a good place to bring marbles and look at marbles owned by others. No schedule, no agenda. I'm not a Facebook person, but I imagine that you could announce interest in several of their marble groups to build an email list. An unmet need is an opportunity!

Nothing will come close to attending a marble show and going room-to-room looking at, handling and discussing marbles. Looking at pics (not always good, well-focused ones) can only do so much. SA marble in-hand and discussing it with the seller or owner x hundreds (thousands?) of marbles builds a very deep and accurate recognition of glass colors, hues, pattern, glass movement and variations in a type that cannot be had on the Internet or in a book.

As far as I know, Mike Petura never dabbled in such things.

WVS

There can be excess colorant in any batch. Some manufacturers watched that more closely than others,