my curiosity has more to do with how three variations of what seems to me to be a continuous theme by the casino can be easily differientiated.

I think the intent of the Mint was for each of these orders to look the same, one being supplemented by the next, as opposed to replaced by it. So a scan would not resolve the issue. Today their is technology to differentiate, but apparently not in effect then.

Without a clear ability to ascertain one issue from another, I'm inclined to do as the chip rack appears to do, and treat them as the same grouping.