Just couldn't resist throwing my two chips worth in on this discussion. I would say that two completely different chips in appearance, whether by center inlay or edge inserts or mold variation ... the chips that look different in design are varieties.

Chips that have identical designs but differ very slightly by degree of same color of the chip; long canes vs. short canes; minute differences in size of denominations, etc. would be considered variations of the same chip.

Here's a question for the experts. A chip with muliple sxs (side by side) different alternating color edge inserts.... let's say red/wht/red, red/white/red, red/white/red. Another example of the same chip is discovered with one of the multiple alternating inserts out of sequence such as; red/white/red, red/white/red, white/red/white. Going through a couple of hundred similar chips, only two chips are found with the red/white/red, red/white/red, white/red/white sequence. Variety or variation? How about Rarity? Is the out of sequence chip more valuable than the "regularly found" variety? Should both variations be listed in a reference catalog?

Sorry my scanner is still non-operational, or I would be able show an illustration. For those of you who have the 2000 Edition of Black's A.C. Catalog, you can see examples on page 38. BOA-5 vs. BOA-5 error and BOA-20 vs. BOA-20 error. As you will see, when the end insert color of one series matches the adjacent series of end color inserts, I've been terming it as an error. Note the end white inserts facing each other at the two and six o'clock position on the $5 error chip and the end pink inserts facing each other at the eleven and two o'clock positons on the $20 error chip. These interesting chips were discovered by Bob Krueger and his information was passed on to me for inclusion in the catalog.