Mineralogy and gold processing techniques from several mining areas of the Nazca-Ocoña gold belt, Mid-South Peru, were investigated to assess the efficiency of gold extraction methods in relation to their mineralogy.
Artisanal gold mining (ASM) is a widespread activity that involves more than 15 million workers [1]. It was estimated that in 2013 there were about 16 million gold artisanal miners worldwide [2]. This number increased up to 20 million in 2017, which represents 50% of the total number of artisanal and small-scale miners [3], with an estimated gold production between 380 and 450 t/year [2]. Artisanal gold represents between 20% and 30% of all the extracted gold in the world [4]. This ratio could be even higher because the commercial activities of artisanal mining are poorly ruled and information can be obtained from field surveys of miners and Artisanal Mining Associations, and from traders who buy gold directly from miners [2].
Gold mining is one of the most important economic activities in Peru, to the point that thanks to this activity Peru is no longer considered a developing country but an upper-middle income country [5,6,7]. Artisanal mining represents about 20% of the total gold produced in Peru [8] and involves about 30,000 direct workers and 180,000 dependents [9]. According to the United Nations Environment Programme (UNEP) [10], these figures rise to 70,000 direct workers and 300,000 dependents. A significant proportion of these people are located in the Mid-south region of the country.