I purchased that book (and as time goes on probably the rest) and it does work. I think it is worth the ten bux. I made the mold and have made crucibles with them, my problem was that I tested them to destruction. My recipie doesn't like iron temps. A word of caution, make really sure that you ram the crucibles up evenly in thin layers, and I would make sure your walls are about a half inch thick. I made mine a bit on the thin side and they are difficult to ram up. My own fault, not the book's. Of course I had to take and modify mine...
Definately worth the money, and will work great for aluminum or brass crucibles.
