Review on 🔧 Optimized ULTRACAL 30 Gypsum Cement - Plaster for Mold Making and Casting, Perfect for Latex Molds! Exceptional Detail Retention (10 lb) by Dawn Fischer

I make shaped stones for rock art. It is easy to mix and if spilled while filling molds or stirring the mixture, it is very easy to clean up. I had 2 problems. First, the stone must be sealed before painting. It soaks up paint quickly and is not easy to remove if you make a mistake. In fact, moisture softens the rock so much that its removal leaves indentations on the surface. Second, I've noticed that even after applying maybe several coats of paint, the stone will still crack if the outer edge isn't deep enough. I try to harden my stones for a few days before coloring them but I'm still having trouble.