A Late Ketland is lock Don Bruton used in my Gillespie that I'm learning to use. It seems great, fired the pan with the original flint that has been fired probably 50 times yesterday morning. Then after 3-4 shots, I got a couple misfires. Looked at the flint, there was a big V-shaped chip in the middle. I thought, what the heck, I'll try to knap it. Tapped it a few times with the brass rod of my starter, got a decent edge, it started firing well again.