Ive been using tile grout...but instead of adding only water, I also add in some elmers glue. The tile grout tends to crack....I noticed when I added in the glue, that didn't happen so much
Thanks. cheap is what I was looking for. lol. I always see tutorials for egg carton stones/bricks, but I never get cardboard cartons.....too expensive! Lol i was pleased to find the trays work just as well for the stone. :)