Gazzer63
Do you actually have some of this black stone flower. Very obscure,
I seem to remember Vah Chef using it in some of his early Tamil videos.
NOT a herb, its a Lichen/Fungi, with no distinct flavour of its own, another name for it is Kalpasi
It may be used by chefs in South Indian BIR, but I doubt the majority of BIR
will have heard of it, or indeed bother with it, because of its rarity and cost!