Rock/stone is the material of castles and fortresses...
and stone fireplaces can be stunning.
And, actually, yours is stunning - but you don’t see it that way.
If I wanted to alter the stone, I would not paint/whitewash - I would cover it with drywall. IMO, it ends up looking really ridiculous when people paint/whitewash stone, brick, etc. To me, it is just not a good look. Personally, I would keep the stone. It is really nice stone that you have there. I don’t know if it needs cleaning; but if it could be cleaned in an environmentally safe way, I might look into that. But if I wanted to cover it / it would be with dry wall - not paint, etc.
This article has DIY info re: how to cover stone fireplace with drywall. It has a lot of interesting info. But if you go that route, I don’t recommend that you do it yourself. I would get some professionals.
https://www.diynetwork.com/how-to/rooms-and-spaces/walls-and-ceilings/how-to-build-a-standard-wall-over-a-stone-wall
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