Good news for you! Yes, you can use dishsoap to cut the water resistant
coating of the paper.
For ideas try this...crush the paper into tight wads to create lots of
creases. Cover the paper with watercolor or ink washes. It will sink into
cracks and create effects like batik or old parchment paper.
Ann-on-y-mouse in Columbus
Art teacher, K-5, retired
Unfortunately, the paper is finished with a slick finish. Do you have any
suggestions on what I might use to get tempera to stick to it? Someone once
suggested dishsoap, have you heard of this?