Liking Lichens - Rhizocarpon geographicum

In an uncharacteristic liking lichens themed post, rather than lots of shots of stuff I don't know but just like the look of aesthetically - here's a couple of shots of one (I think) I do know. This is Rhizocarpon geographicum, very common on hard siliceous rocks apparently. Here I see it often on dry stone walls and big boulder stones in the Charnwood area

Bradgate Park - 26/03/2018

Altar Stones - 26/02/2019