Alan

Not German, but too out-of-focus for me to tell. Maybe Akro, possibly Vacor.

The problem with the "End of Cane" idea is that it doesn't benefit from a working knowledge of cane-cut marbles and the variables in trimming the cane in preparation for the next cut or a hurried marble-maker. In the final analysis - it a cane-cut marble. The construction of cane, pulling it, the opacity of the rods, how much the cane was pulled (decreasing color density), how heat was managed between cuts.... all this affects the appearance. I think it better not to hope that a marble is a special kind/meets some special nuanced definition. There are a lot of assumed, but incorrect, beliefs on cane-cut marbles. Words are used to describe them that cause folks to believe in concepts that simply aren't accurate.

Quartz and glass have different melting points, and therefore different coefficients of expansion (COE). (Yes - you can make a "glass" from quartz). Attempts to mix the mineral quartz with glass (two fairly different melting points) will result in internal stresses as the glass cooled. Those internal stresses are what cause annealing fractures.

Like several other words used in the hobby, "aventurine" is misused and abused. "Aventurine" is a mineral - a form of quartz. The reflective flakes in glass marbles are NOT aventurine, despite how people have come to dream of it as a rare substance. Those flakes are excess colorant or chemical precipitate from chemical reactions.

They have no individual "names", and I think it is best kept like that. The naming fetish has gone a bit far.

You should beatbox that.

If you Maglite it, it will be purple glass.

At the New Philly show 20+ years ago, a guy said he had some Akro in his van he wanted to offer me. In the van he opened a wood Army footlocker that was FULL of blue/yellow Popeye patches. I have no idea how many thousands of them were in there, but it was a really, really big number. He said the footlocker couldn't be moved (and wouldn't stand the weight of the contents if moved). He begged me to buy some...."Name your price!" but I walked. That was just one digger. The total universe of dug blue/yellow Popeye patches is HUGE. Think >15,000. and well beyond. I think they are just errors that were dumped. Nothing more unusual than that.

Yes. I bought a passel of them years ago. Andy did great work.

They are known up to 1".

No, they are just poorly made marbles. That happens in mass production. They were usually discarded as refuse.

Marbles were commonly used as claw-foot balls back in the day.

(Noting the seller to avoid their auctions)

The "concept" is emptying the glass tank of most of it's contents for a different batch of glass. In practical reality, it was used somewhat as a euphemism for something else related to accounting.

Not a Popeye.

I do - but generally just before tight turns.

Master.