1. ChemistryLeaching is the loss or extraction of certain materials from a carrier into a liquid (usually, but not always a solvent), and may refer to: Leaching (agriculture), the loss of water-soluble plant nutrients from the soil; or applying a small amount of excess irrigation to avoid soil salinity Leaching (chemistry), the process of extracting substances from a solid by dissolving them in a liquid Leaching (metallurgy), a widely used extractive metallurgy technique which converts metals into soluble salts in aqueous media Dump leaching, an industrial process to extract metals from ore taken directly from the mine and stacked on the leach pad without crushing Heap leaching, an industrial process to extract metals from ore which has been crushed into small chunks Tank leaching, a hydro metallurgical method of extracting valuable material from ore In-situ leaching, a process of recovering minerals such as copper and uranium through boreholes drilled into the deposit Leaching (pedology), the loss... from wikipedia.org