We bought a bag of rough rocks for tumbling and we had a bunch of black jasper in it. The only time we would ever want to tumble black jasper would be if it was Scottish (we sell rough Scottish jasper by the 500g here). Tumbling up international stones is fine if we get the return on them, but in this case it is not worth the electricity and grit costs for what they would make - no matter how pretty they are once polished.
These are nice, angular pieces. Black jasper would look like basalt if it didn't have that same fracturing that chalcedony has. These stones are much smoother already than they look. It is a nice fine grain.
Obviously these are unpolished and the price will reflect this. Further things that might interest you include our Jasper Stones category and our blogs about how we collect Scottish rocks.
