Resumen
The mineral aerosol fraction in the southwest zone of Mexico City is about 25% (40µ g/m3 approximately) of the total of suspend particles. When analyzing the mineral fraction by X-Ray Difraction, the main compounds detected are quartz, tridimite, cristonalite, feldspars, calcite and irin oxides, furthermore the elemental chemical analysis by X-Ray Spectrometry confirms the correspondence with crystalline phases revealed by Diffraction.