Btw, you advised me to 'do some research'. Well, I do, but I have been busy with botany., and how chemicals from plant roots and chemicals formed by lichen are able to attack and dissolve rock like granite.
Just so you know I am not sitting on my flat behind doing nothing, lol.
see some of these snaps of rocks for natural shine, soft edges, and a 'vitrified' look in parts
these are just seaside/shoreside rocks