When Argosy Empress, Joliet, IL moved from two boats to a barge they scrapped the old roulette chips and brought out a new rack.

The new chips picked up where the old ones left off I, J, K, L, I think. Maybe it was J, K, L, M.

I think there are all kinds of circumstances that could account for 'unmatched' or 'out of order' roulette chips.