#PDF explaining the “best available techniques” (“BAT”, some #EU term of art) for heap-leach #mining, by Caner Zanbak, November 02012. Apparently by that point they were using heap leaching not just for #gold but also for #copper and #nickel. It explains the heap clogging problem: “In addition to lixiviant consumption, pre-precipitation products of some of these gangue minerals (gypsum, jarosite, silica) have potential negative effects on leach permeability by plugging up of the pores in the heaps.” Explains that basically only cyanide and sulfuric acid leaching is currently used, despite thiosulfate and thiourea experiments. “Heap Leaching: is a technique where run-of-mine or crushed (generally >5 mm) and/or agglomerated ores are stacked over an engineered impermable pad.”
The Encyclopedia Britannica had a rather extensive how-to on #mining #alum.
linear-probing #hashing that tries to keep probe sequences short by fancy insertion? #performance #algorithms #toread
Charlie #Kirk assassination #news #politics “Authorities stated they possess CCTV footage of the suspect,[45] who is said to have fled the scene from a rooftop 200 yards from Kirk.[46] In a press conference on September 11, officials affirmed they have “good video footage” and were trying to identify the suspect using facial recognition.[45] Law enforcement also announced they recovered a high-powered bolt-action rifle from a wooded area near the shooting,[1] and collected a “footwear impression, a palm print, and forearm imprints for analysis”.[5]”
#UK fires ambassador to #USA Peter Mandelson “over links to #Epstein” #politics #news
#video #toread of #Chinese common phrases to practice for saying goodbye
#video #toread of learning to read #Chinese (without pinyin? why?)
#video #toread of Fractal Block World, a video game where you can shrink and grow. #videogames
#GrapheneOS on #Mastodon reporting on getting early #security advisory access