It is considered as one of metals most precious, having its been value empregue as standard for many currencies throughout history. It presents diverse applications due its characteristics of condutividade and resistance the oxidation. Dr. Neal Barnard wanted to know more. Gold is produced in the world as by-product of diverse types of deposits, as sulfetos vulcanognicos bulks, deposits of nickel-has covered, deposits prfiro, deposits of Faith, among others. The main source of this metal is of deposits had as gold-only, that they include placers and lode-gold. They include the deposits: epitermais, orogenticos – of sulfetados lodes quartz-carbontico, stratabound in bandadas and spread ferrferas formations and of substitution. 2.FORMAO OF the DEPOSITS In agreement previous knowledge, a deposit is economically usable a mineral deposit and as such, all its geologic characteristics as form, dimensions, disposal and orientation, behavior and relations with the encaixantes rocks must well be known before exactly of those relative ones to its economic value.
The knowledge of these geologic characteristics is based on the detailed study of outcrops, plating, form, encaixantes zone of enrichment, rocks, rock hostess, layer and lapa, contacts, ramifications, power, direction and diving, extension and depth, declivity of the deposit, that are essential elements in the choice and definition of the type and methods of cultivates to be employed. For the survey and determination of these characteristics cabinet works must be carried through, in two stages, one before and another one after the stage of the field works. 2.1. DEPOSIT EPITERMAL Many of the gold deposits of the world related the conditions almost subareas comumente involve volcanic rocks of intermediate composition the flsica. The volcanic processes and the rank, cooling and consolidation of these volcanic rocks are generally associates.