All the rocks we love

"Children love rocks. Rocks appear in jacket pockets, on windowsills, in the car, in their hiding places, and most often, in their little grips. Rocks are universal -- they can be found in all climates, countries, and communities -- making themselves available to anyone who craves the tactile pleasure of holding a perfectly sized, unfragile, unowned object. They can be collected, compared, stacked, plunked into water, painted, and shared. This bo...