USA Rock.

i have become a member of a USA group  - wow they are spoilt for rock and knapping is huge across the pond.

Yup, I've tried many kinds of it, Novaculite, Chert, Dacite, Obisidian, Rhyolite and a few others, knaps a lot easier than flint too, Which kinda makes it twice as jammy.

is there a uk supplier of USA rock? they seem to make some great looking points.

Only one I believe.
https://sites.google.com/site/hangingwood/home/Flintknapping-Knives

I also know a cheap place in the US.

Thank you, i am also thinking of heat treating some flint under a layer of sand on a log fire, all the flint i have has no ring to it and it fractures real bad, i think its all frost damaged - i wonder if heat will make a difference.

I've heat treated in the past, the best advice I can give is, the thinner the flint the less likely to crack. The longer the you heat treat it the softer and waxier the flint gets.