When I see a Pelty marble which has two colors of ribbons but not a flip-flop, _that_ is when I start thinking Kokomo.
When people try to turn perfectly pelty bubbly glass into Koko just because it's bubbly, I roll my eyes.
But no two ribbon colors with no flip-flop? That's when I want to start saying Koko for what everyone else thinks is Pelt.
Feel free to roll your eyes.