I'm the guy looking into these chips. The seller, who doesn't seem to know much about them, claims they are wood chips. The pics he sent me clearly read 'Portland Card Co' on the chip boxes. I can't find any evidence that PCC made wood chips and posted such on the ChipTalk board. Based on some of the responses there, I'm wondering if these are really clay. I'll go and check them out tomorrow, but any history on these chips you guys can offer in the meantime is appreciated.