Precious metals in your shit.

http://motherboard.vice.com/read/scientists-want-to-mine-our-poop-for-gold?trk_source=homepage-lede

Excerpts:
"Every year, Americans are flushing a fortune down the toilet. Literally. More than 7 million tons of biosolids—treated sewage sludge—pass through US wastewater facilities annually. Contained within our shit are surprisingly large quantities of silver, gold, and platinum."

...

"But that’s starting to change. Earlier this year, a study led by Paul Westerhoff at Arizona State University profiled over 50 metals in biosolid samples from 94 wastewater treatment plants across the US. Most samples were substantially enriched in rare and precious platinum-group metals, silver, and gold. Extrapolating from their data, the authors worked out that the waste produced annually by a million Americans could contain as much as 13 million dollars worth of metals. That’s over four billion dollars worth of gold coming out of our collective arses every year.​"

...

"To do so, the team is working to modify extraction procedures used in industrial mining to leach metals out of minerals. “Traditional extractants will behave differently with the organic matter [in biosolids],” Smith told me over the phone. “But if we can find an extractant that does a good job, this procedure may be incorporated into current biosolid treatments.”"





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Oh, I have some ideas on that:
1. Blend the shit with water until it's a thin, disgusting slurry with a unique aroma.
2. Add a mild acid to dissolve the solids. Let rest for a few hours/days.
3. Use some centrifuges (e.g. used in Uranium-enrichment) to separate the metal-nanoparticles from the solution.
The result is a soft, mineral-rich, clay-like compound with traces of biological matter.

4. Transfer to a ceramic-crucible and into a vacuum-chamber. (Reduces boiling-point dramatically.) Heat to ~500°C to evaporate most of the remaining organic components. (Beware: You will get steam that smells like shit.)
The result is a porous, brittle, sintered block of metal-particles with traces of organic impurities.

Erm... I'll leave it to the metallurgists from here.
(I would melt it down and separate the phases with another centrifuge, but that's most likely more expensive than the metal is worth.)









You may now commence with tasteful jests about mining someone's arse...