The "value" codes is more or less a guide to how scarce the chip is. Since Dales book and with ebay, a lot of these chips have come out of the woodwork. The quality and condition of the chip plays a big roll in the value. Antique clay chips with value codes of ABC&D are common chips and they will need to be in near perfect condition to get the price if at all. Antique clay chips with value codes E will follow the value codes very close and the chips are worth more if in excellent condition. Antique clay chips with values FG&H are hard to find in any condition and the value is much higher than what is listed. Here is Dales value chart and a note that Clay composite chips do not have values past "I" but the price now for an "I" valued chip would be much higher in any condition example would be Crest & Seal Antique clay chips. Chips with "J" values and up are usually Ivory coded chips and many are worth much more than what is listed. I hope that helps?