Those Neolithic Norwegian arrows found beneath a melting snow-patch up in the mountains:
I don't know anything about Neolithic arrow heads, but these seem to be very crude, and much larger than the delicate arrow-heads assumed to have been made in the UK -- normally from flint. But in an area in which there was no flint, might not the arrow heads have been made from whatever handy rock happened to be lying around the place -- rhyolite, slate, shale, or indeed any other fine-grained or glassy rock capable of giving a sharp edge?
Craig Rhosyfelin, maybe? Would it be too outrageous a suggestion to say that the so-called "quarry" might have been used for the manufacture of knives, cutting edges and arrow heads? Does the stratigraphy in the dig give us any clue on this? Is there a debitage which might be explained as the debris from tool working? No doubt all will be revealed when MPP deems the time to be right...