I'm leaning Vacor on the big one. Not really getting a handle on the one you took individual shots of. I don't recognize it as older, so my default answer would be newer ... but basically I'm not getting a good feel for the structure.
Pretty sure my computer is not supposed to be making this noise. Gonna try to figure out what's wrong. Might be offline for awhile. Hold the fort down while I'm gone.
Onyx originally meant slag to Akro, but around 1930 they switched their operations to making corkscrews, and they changed the Onyx name over to the corks.
And you have one of their corks.
We did some of that in this thread: http://marbleconnection.com/topic/20318-marble-comparison-thread/
Anytime anyone wants to bump it with another example, that would be great.
But Atmospheres were handmade and that sure does look like a machine-made style .... now I'm dithering ... but at least you have an interesting idea to consider.