200 year old vaulted cellar is plastered
English is not my main language and I am not familiar with any professional terms so pls have patience with me.
8 years ago I bought this house and it came with a masoned basement that was already sealed like this. I have no idea what exactly was used but it looks to be a combination of plaster and white paint. The basement feels damp and stuffy, but not unpleasantly so.
A lot of this houses interior ''logistics'' don't really make sense so everything might be possible. During it's lifetime lots of more or less professional people made changes on it. At the beginning the ceiling and parts of the wall were very crumbly and sandy so I've avoided using it since it covered everything with wall dandruff. Over the years it stopped falling off on its own but still comes loose by the slightest touch.
I've also included pictures of the fluffy stuff that has formed where the plaster fell off. I am pretty sure its not mold but some sort of gypsum/mineral crystal, I didn't want to touch it.
However, TLDR: What should I do with this remove/renew? My plan is to use the basement for pottery which will make the room more damp, I am worried more will come off. Or even pose a health risk.