There was an account of a fellow cutting into the cellar wall in an old house in a small French town and hundreds of coins started falling out from the 1300s—1400s.
If you can recall that do you know any details?
I don’t, but maybe a web search would turn up something. OTOH, there are lots of fake or botched stories about finds, such as a story about thousands of intact Roman-era human remains that were exposed by a dig during Mussolini’s projects, but started to decay immediately when exposed to air, and were allowed to turn to dust. That’s just some wartime propaganda.