Seaweed??

Mr U&L and I went for a day out today, first to Chailey church, then onto the Bluebell railway.
Chailey church was beautiful, and as with many of these wonderful rural churchyards the old gravestones were covered with an amazing array of lichen, including this specimen that looks for all the world like sulfurous seaweed clinging to rocks at low tide!
I don't know the species, but I will try to do some id, although Lichen identification is recognised as a minefield!
I have included a shot of another yellow lichen in my extras. and a shot of the train at the Bluebell railway, framed by the light on the bridge.