The name says it all. Very hard type of plaster, easy to use, bright white but easy to color any shade. For model train scenery it is a bit hard to work with at first but its hardness makes it better in the long run for its durability. I bought it to cast miniature bricks, really great results. Tried it as a counter tile grout, works nice with pastel color added, can't say yet how well it works because it has only been in place 1 month but a friend in the tile business loves it so far. Gave some to my dentist to play with also, no feedback from him, must be nice due to the bright white color!!

Best casting material I've used to date. Easy and reproduces the finest details crisply and cleanly I make ckhess sets and all the players like the weight permastone gives the pieces.

I love this stuff! it works best when mixed with a bit more water than suggested, giving greater flexibility when pouring, and offering extra time to get a mold poured successfully...

I have yet to make this stuff mix correctly and work. When it is as thick as cream and I pour it into my molds, it does not dry. I have wasted a lot of money on this product.

I very much like the permastone. It's easy to work with and has a very fine finish. I also like the weight. I wish though it would be available in bigger quantities.

I use the product for making molds. The only complaint I have is knowing when the setting time is up. It's different with every object I use. Hardens fast and is good for paper casting.

Great product...dries very hard after full set (give it a few days). Still scratches slightly on surface, but overall, much harder that regular plaster. Great detail in molds!