Thanks for the tip. I went to my local art store and picked up a package. 4, 4"x6" pieces compressed to less than 1/4" thick. Expand to 5/8" for $4.50.

Played around with one and it seems free of the odors and slippery feel that others seem to have. Soaked up some good water and tasted it. No taste added. Seems like a winner.
thanks again.