SWEET ! You don't see much of that high grade quartz turning up. I refer to that material as "milk glass" quartz due to it's pure coloration, and great knapping potential. We have found a few smaller well made points of similar material up here, but none as large as that beauty. HH
I never could figure out why quartz was used since the few that I ever found were thick, stubby, and didn't look very deadly (except one small triangle that was thin and well-formed). I couldn't see how they could have been fitted to a slim arrow shaft. So, I wonder if my "fatties" originally looked like the killer yours is? Did they eventually degrade; or ... were they always thick, stubby, and ugly? Makes me think a sharpened stick would have been a better tool/weapon than quartz. Then I see YOURS! Wow ... that is a beautiful -- and quite obviously dangerous -- point.