MyLamyyy

Forget stone casting. I sculpt my stones by hand. You get a different stone each time, and you pick up different techniques as you go along.

I typically go for a recipe that resembles sandstone. Approximately, I use 3:2:3 proportions of Sand, White Portland Cement and Peat Moss respectively.

If you really want light rocks, I create an inner mold made out of plastic bags and chicken wire, and I surrout that with a mix of perlite and cement. This will be about a 1 inch layer (thicker or thinner depending on the size you are going for). You don't really have to care much about the aspect, because when it dries, you will "smear" the tufa mixed I told you about earlier.

For the color irregularities, I use a yellow/rust like dye for a first layer, then I spear on a layer of pure white.

Hope this helps

"Cast Stone" is a cement recipe using crushed granite or marble or limestone.

mylamyyy, I've used some crushed marble and granite in a couple of recipes for small jewelry pieces. Nothing bigger than a couple of inches. Can't help you with anything bigger. Billie

Cement can be polished (always wet-sand as the dust is deadly), but it's a lot of work.