the linked 'gas marble' article is good too, in particular the construction method for the marbles > Timounay found that if the frame was wide enough and the m

the linked 'gas marble' article is good too, in particular the construction method for the marbles > Timounay found that if the frame was wide enough and the microspheres were at least several hundred micrometers in diameter, then lifting the frame generated a gas marble. During lifting, the film on the frame would spontaneously fold in on itself and detach to form a gas marble that would drop to the liquid surface below. “The full mechanism of gas-marble creation is not fully understood for the moment, but their creation is reproducible,”