I'm a paperweight collector of the non-flak variety! I actually started with "coloured Victorian glass" and anything else that took my fancy as long as it was cheap enough, but then I got hooked on the "domes with coloured bits in".
Although I am now both a "generalist" and a "specialist", I had never found myself drawn to marbles as a collecting theme. But in the past year I have become aware of "Art Glass Marbles" and I can see that people would indeed enjoy collecting these as much as I enjoy my own focus.
Here in the UK, I dont get to see many Art Glass Marbles, but I have recently checked some websites and I was reminded that Teign Valley Glass in Devon, UK started out in 1981 as Marble makers. They provided thier sister business, "House of Marbles" with "Victorian replicas". Their products are now "worldwide".
Neverthelss, it does appear that the main following is still within the US, and that seems to be borne out by the fact that almost all of the sites listed under the subject are US-based.
However, Sweetbriar Gallery, a major UK paperweight dealership, are now offering some items from Cuneo Furnace, a US Marble maker. And I have to admit that those items are tempting me into the field! The ones currently shown in the Sweetbriar website are all 2 1/4 inch and are very well made with coloured swirls and filigree twists. It is the size and form that, with my paperweight collector hat on, draws my interest.
Apart from that, the closest I actually have to a Marble in my own collection is a 1 3/4 inch diameter, 1 1/4 inch high 'paperweight' with an "extremely artistic" blue and yellow-green central swirl. I say it's "artistic" because I made it - during a one-day course at a glass studio. The instructor said of it, "Well ... we'd call that a marble"!