Comment from John Hutchison
"Bob, awesome report.
There’s also bead lightning, I used to make. I called them 'fizzy balls' - as one could see 'fizzy' actions and color changes, this was medium voltage.
In some cases, the balls where tiny, about less then 5 mm and they would change color. Also bright balls would be from exploding aluminum wire, or copper.
The larger free floating balls where very bright and would last maybe 10 seconds and moved fast."