I ordered some garden sulfur for making black powder and was going to purify it. It says it 90 percent pure. Will it work or did i waste money? I have always purchased good quality sulfur but its getting more and more expensive so i thought i would experiment. I have been corning my gun meal and it makes really good powder. Better than some store bought stuff, well faster any way. I figured if i can purify it, it should be good. Any thoughts.