Hole and the rocks

As I was painting water this week, while I came across searching for rocks near the shore. I was looking for a special rock I can relate to, until I found a small stone with a natural circle formed in it. I became interested in how long it took this material to form the way it is now. Also I got interested in the stillness these rocks represent to me and how I find them and their smooth surfaces to have a certain level of kind energy.