In an earlier post I mentioned that i used to be able to get Texblast sand, where the gravel size was about the same size as a BB pellet. Today I wemnt a a landscape supply place and was directed to their coarse sand pile, still to fine a sand to suit me - but the 4 inches of rain we had yesterday had left a residue of very coarse sand or more accurately very small gravel on top. I skimmed this stuff off the top and brougt it home. I'd bought a giant strainer - $4 at Wallyworld - and the mesh was just right for separating this from teh sand that i nevitably also scopped up. The gravel came out prety clean - I am thinking it's just dirty enough to be nourishing to the plants! Halfway through the $5 worth of sand, and I already have all the gravel I need! And having been a geologist, I can tell that the gravel is 100% quartz.