Rich - As I noted above, several club chips of the Crest and Seal types are known in at least two of the three known edge finishes. Unless someone has additional information, the only possibilities I can think of to come close in answering your question is either duplicate orders; large orders where all trays needed to be utilized, or customers' request on large orders. I would love to say something along the lines of time frame of production (round early; square late), but my studies of production dates with all three mold edge finishes does not prove this. I've applied for a government grant for further study, and got some silly reply handwritten on lined note paper using green crayon and never got my original chip that I requesred signed by Clinton. I can only suggest that you enjoy the chips no matter how they may have been finished on the edge and that you do not become a lunatic such as I. Otherwise, you'll find yourself wondering why certain glues were used to affix inlays in certain types of production (two-step), or even bringing the chips to your friendly, favorite Dentist for X-rays.

JB