i bought a couple 20# chunks from a dealer. considering the cost i decided to slow down. and ive been getting some great spalls instead of ruining it. i stopped using my leg, i found i get better flake travel if i hold it freehand. then once it is thinned out and i need more accuracy i will lay it on my leg. jasper isnt that tough of a rock either. well not compared to some of the ct and texas concrete im used to.