抄録
The partition of silver between solution and electrum was used to estimate H2S concentration in the Kuroko forming solution. The calculation was made for a 1 molal NaCl solution at 250°C. The Ag/Au ratio in the ore solution was assumed to be identical with their crustal abundance ratio. Electrum containing as much as 35% silver can be deposited from the solution with aHS-=10-4.5, which corresponds to 100 ppm as H2S at pH5. Gold is dissolved as thio-complex Au(HS)2-in the ore solution.
