The bottle is not cased, I don't believe any of the others are either.
Your zig-zag is more along the lines of my precious baby fish, John, with swirls of different colours, not a main colour mixed with clear to sort of make it paler, like this piece.
I'd suspect this is simply an early-ish bit of (probably) American studio glass, not neccessarily early in date, but early in the career of the maker.