I don't know!
I _think_ so ... maybe as long as the ribbons touch?
Does everyone require baseball ribbons to touch? Or come close?
(Some people don't require blue ribbons.)
I don't know much about sulphides.
Do you have a handheld blacklight?
If I understand correctly, old sulphides will fluoresce and new ones won't. (Can someone confirm? Am I overgeneralizing?)
These are contemporary handmade ones.
I'm going to move the thread over to the main chat forum to see if anyone recognizes makers.
Sometimes people will sign their work. Do you see any initials etched into any of them?
What do you have in the way of Pelt patches?
Classic PPP's and Realers would of course be welcome.
I'm also interested in seeing some of the less common or less recognized and even the suspected but unconfirmed ones.
When I saw the title of Jelle's Micro Marble Run thread, I thought of a micro machine, not micro marbles.
Tiny marble machines using small marbles -- maybe ball bearings for speed -- could be fun.
You could keep one on your office desk.