Lichen knot

My lungs are a bit knotted as I'm fighting off Rich's lurgy. I'm guessing the insides maybe look a bit like this although thankfully, not as colourful.

Little Dog kept trotting round my feet expectantly this morning as I couldn't really be motivated to get outdoors.  I feel better now I have and did love how this old knot has been gathering nature - seemed a bit like it was fossilising.