I found a big patch of floating coconuts once. A really big patch but not as big as that pumice patch. I kept about two five gallon bucket full of them. Then there is a big eddy in the ocean North
East of Hawaii. A lot of glass floats, and coconuts there. The coconuts are all rotten by the time they get there but the glass balls are cool.
A pumice patch would scare the shit out of me.