This gravestone is in the Churchyard of St Peters Church Old Woking. The gravestone was from the 19th century.
Caution: Do NOT use iSpot to identify fungi to eat!
Some fungi are very poisonous so a mistaken ID could have serious consequences.
No interactions present.
Any chance of a clearer photograph to show details?
The blackish one is a Verrucaria, but again need to see details for closer identification.
There are several things here and I wouldn't say for certain that any of them is a Xanthoria.
Also "Leafy Xanthoria" is not a generally recognised common name - better to give the Latin name for precision.
I know Opal are using "Leafy Xanthoria", but actually all our Xanthoria species are leafy (foliose), so really it is a very poor choice.
Good luck with the survey, but I recommend you don't use gravestones, as there are too many other variables involved.
Lat/Lng: 51.3008543, -0.56019330000004
OS grid ref: TQ004567