This is a good idea. Except, we have snow on the ground right now. Not sure we'd be able to find any. lolWe used to, but the last few years we drive to the beach & hunt of r egg-ish shaped granite rocks & take them home & paint & seal them. Not too big & the girls keep them in their bedrooms. I sharpie the year on the bottoms. We have done bigger ones & put them in the garden =)