heat treatment was either too long or too hot of a temp. swan river chert responds better to a low heat and longer treatment. if heated to long or to high a temp becomes brittle and or powdery like.☺
also a hard granite hammerstone works best for removing larger flakes as it absorbs some of the initial impact and your left with bigger thinner blade blanks.
I have mad respect for this guy's experience and interest in his field, but man he sounds like the G-man
heat treatment was either too long or too hot of a temp. swan river chert responds better to a low heat and longer treatment. if heated to long or to high a temp becomes brittle and or powdery like.☺
also a hard granite hammerstone works best for removing larger flakes as it absorbs some of the initial impact and your left with bigger thinner blade blanks.
All these guys have sticking plasters and a lot of patience