Mexico conducts continuous regional explorations and detailed evaluations of its Pacific metallogenic provinces. Efforts of the past few years have resulted in 300,000 mi² (775,900 km²) of Landsat imagery coverage, photogeology, surface and subsurface geology, surface and aerial magnetometry, geochemistry and diamond drilling, plus underground mining methods of exploration. Isotope geochronologic determinations were performed on 719 rock samples, mostly from the Sierras of the Pacific provinces.

Economic geologic investigations resulted in the discovery of 183 polymetallic deposits, many of which are already in operation. La Minita, eastern State of Michoacan (Ag, Ba, Zn, Pb; 2000 t/d), is a notable example. Fourteen important nonmetallic orebodies were also found, some of which are already in production. One of these is Teliztlahuaca in the State of Oaxaca, where reserves of crystalline graphite, estimated at more than 2 MMt, assay at 4.25% and are processed by a 600 t/d plant.

The total reserves of in-situ metallics amount to 124 MMt, with a value of US$8,680 MM. They include Au, Ag, Cu, Pb, Zn, As, Bi, W, Fe, etc. The total volume of in-situ nonmetallics is 78 MMt, valued at US$3,600 MM. The most important of these are barite, borates, gypsum, marble, anthracite, and magnesite. Geologic and geophysical maps show the locations of outstanding deposits.

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