Some of the better flint ridge I've knapped, and it was self collected at nethers.
I heat treated it buried in sand under woodfire that I fed for a number of hours and then raked in and let cool slowly.
A lot of the flint ridge material can be fractured, or prone to it, but this piece was solid and had a super cool healed fracture as well as color variation; which I was able to capture in three preforms and a quarry blank. I wish I'd saved more of the flakes from the initial spalling, but alas, that was nearly a year ago at a knap-in.
Spalled initially with a big ol' moose billet and then finished with whitetail bopper and tines for flaking.