Abstract: This paper describes the genesis, structure and classification of natural zeolites, including their most relevant properties such as porosity, adsorption and ionic exchange. The use of natural zeolites in the treatment of effluents containing heavy metals is reviewed based on current literature. These uses are focused on mineral-metallurgical effluents and mercury pollution related to artisan mining activities. The study shows that natural zeolites are efficient in removal of heavy metals in metal mining effluents, can be produced and improved at a low cost, and can also be used to adsorb mercury vapors from ovens used to fire amalgams.