MINERALOGY AND GEOCHEMISTRY OF CONTAMINATING HEAVY METALS PRESENT IN MINING SOILS OF SOUTHERN CHILE

Abstract

In the Southern part of Chile, with mild and a rainy climate, high levels of heavy metals have been detected on many gold placer deposits, many of them contaminants, which means a human´s life risk and as a consequence, a damage for the trofic chain of its environment. The main heavy metals found as a result of the study are mercury, lead, cadmium, chrome, tellurium, indium, zinc, iridium, palladium, zirconium, rubidium, tin, cobalt, copper, platinum and gold and on the other hand, some not very common elements such as cerium, praseodymium, gadolinium, neodymium, samarium and lanthanum. The type of methodology used on the characterization of the associated mineralizatium consists of testing each representative sample to a granulometric separation, statistical parameters analysis and a mineralogical analysis using a binocular magnifying glass, a pethrographic microscope and SEM/EDX. The chemical compound has been defined by means of X ray fluorescence and michrochemical analysis. The results of the study about gold placers in the Southern part of Chile are presented. Heavy metals, minerals and its classification are an important part of this research project.