Mudlarks, or I guess mudlarking, is something I’d love to do and I am very disappointed in myself for not discovering this kind of history searching while I lived in the UK years ago. It’s a good article, and worth a read. Plus theres a few really good you-tubers that are devout mudlarkers worth checking out.

https://www.frommers.com/slideshows/848024-mudlarking-in-the-thames-might-be-the-best-thing-i-ve-done-in-london