Looking for a little chip I.D. help. By looking at the photos below, could anyone tell me what these chips are exactly? They measure 41mm in diameter (1-3/4") and they are somewhat "soft". I think they are clay (not sure). Many of them appear to be warped, but with the right amount of pressure - and careful not to crack them - they can be "un-warped". That's how soft they are. They feel almost like a "rubberized" clay substance. I picked these up (and a whole bunch more) at a local garage sale and I was just wondering how old they might be and/or if they are of any value? Any details would be appreciated.

I'm putting this out to all you experts and I'd be interested in any input you guys could offer about these chips. Thanks!