Take a look. Duck effigy and arrow shaft straightener made of quartz. Both the bottom and behind the head are grooves to straighten(bottom more so). In the side of the head is a circular hole maybe to sharpen or grind either end of shaft?
juddzilla,
What you have there is a piece of 'bull quartz/milk quartz/massive quartz that has broken in the "cloud shape" of a rubber ducky. I see NO human crafting to it.. a neat piece, but NOT human made... Mother nature had her "hands" on this, that's all.
A shaft abrader will be smoothed in a groove from repeated use. Usually made from some form of sandstone... nature's sand paper. Quartz is to hard to be used for this ( unless you had diamond arrow shafts- quartz wouldn't wear in a groove being used on wood)
here is a link to a real shaft abrader. http://forum.treasurenet.com/index.php?topic=407674.0