Thats cool and great pics. We see a lot of heat discoloration on cherts in archaeologcial assemblages. I'm curious why, around here in central PA, they heat treated jasper a lot. it seems to be a very high qualty material without heating, but then I'm not a knapper (I am, however, a good napper)
I might use some of you pics in a publication. If so, i will contact for permission
Dave