TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: In the method (M1), the precipitates of zinc and manganese are dissolved in an acid or ammonium sulfate. The method (M1) further comprises contacting the zinc with hydrochloric acid to produce zinc chloride. In the methods (M1) and (M2), the step of precipitating the zinc and manganese comprises adding sufficient base to adjust the pH to 6-8 and providing an air oxidant to the substantially silica free brine. In the method (M2): the step of dissolving the zinc and manganese comprises providing a mineral acid sufficient to dissolve the zinc and manganese precipitate; and the step of recovering the zinc by electrochemical means comprises plating an electrode with zinc metal from the zinc solution. In the method (M3): the zinc is removed from substantially silica free brine by ion exchange; and the step of oxidizing manganese to produce manganese dioxide comprises electrolytic deposition. In the method (M4): the step of extracting manganese and zinc from substantially silica free brine comprises extracting the manganese and zinc with a solvent comprising of phosphines, phosphoric acids or phosphinic acids; the step of recovering the manganese by electrochemical means comprises plating an electrode with manganese metal from manganese zinc solution; and the step of electrochemically removing the zinc means comprises plating an electrode with zinc metal from the zinc solution. In the methods, the step of selectively removing silica and iron from the geothermal brine comprises providing iron (III) at a pH of 4.5-6 and precipitating the silica and iron from the brine. EXAMPLE - 1.32 l Synthetic brine was placed in a 2 l reactor and maintained at 90-95 degrees C and sparged with air at a rate of 2.25 l/minute. The reaction was stirred for 60 minutes and the pH of the solution was monitored. After 60 minutes, a pH of 2.05 was achieved. To the brine solution was added 9.73 g of a 20% slurry of calcium hydroxide, that raised pH to 5.4. The brine and the calcium hydroxide slurry were mixed for 30 minutes during which time the pH decreased to 3.4, at which time 2.56 g of the 20% slurry of calcium hydroxide was added. The addition of the slurry increased the pH to 4.9. The mixture was stirred for another 20 minutes, after which 1.21 g of the calcium hydroxide slurry was again added, and the pH was increased to 5.3. The reaction mixture was allowed to stir for an additional 70 minutes, and the solid was collected and weighed. The solid comprised 98% of the iron present in the brine and 99% of the silica, and additionally 2% of the manganese present in the brine was removed.