There’s a lot more info on their project page https://feministhackerspaces.cargo.site/Clay-PCB-Tutorial but I think it’s important that I provide context re the PCB being part of their disaster survival backpack! That had lots of other things in it too, tho unfortunately I can’t find the video about it now. But yeah, so the PCB was designed for a kinda worst-case scenario.

As regards the urban mining, yeah it wasn’t quite what I expected: “[we bought] silver paint, commercialised by a German company, that is made with waste silver powder collected by jewellery makers. It’s like an urban mining technique of silver dust.” I was expecting them to find things and extract silver from them!