{ "items" : [
    { "id" : "http://dbpedia.org/resource/Hydrometallurgy"
      "properties" : {
        "http://www.w3.org/2000/01/rdf-schema#comment" : [ "Hydrometallurgy is a method for obtaining metals from their ores.  It is a technique within the field of extractive metallurgy involving the use of aqueous chemistry for the recovery of metals from ores, concentrates, and recycled or residual materials.  Metal chemical processing techniques that complement hydrometallurgy are pyrometallurgy, vapour metallurgy and molten salt electrometallurgy."] } } }
