I visited an Indigenous heritage site today that I have visited every few years by habit. Today the flat beds of stone were prominently exposed with the surrounding grassland totally eaten down to the ground I suspect by local Grey Kangaroos. Grinding grooves are created in the process of grinding shape and edges to stone implements, crushing ochre and grinding seeds are some of the known uses.
I was disturbed however to see a nearby, un-grooved as far as I remember, rock that had been smashed with a melon sized rock which was located nearby..
The rest appeared as they had last time I visited with a considerable amount of washed in sand grit and leaves in the large bowls..