There’s an old saying in the north of the UK – “where there’s muck, there’s brass”. So here’s a modern Japanese re-spin on it: where there’s sewage, there’s gold.
The sewage in question is from Nagano Prefecture’s Suwa Basin, a region where a lot of machining factories and metal-plating outfits are located, and apparently the resulting sludge has a higher concentration of gold than high-grade ore. Ker-ching!
I believe Providence, RI was looking at something like this awhile ago too. When it had a going jewelry industry that is.
..and after the Marsh gold refinnery (oops, refinery) in Innsmouth had been, uh “shut down” by government agents? ; )