Notes from the AGS field trip to Zacatecas, Mexico

Participants on the AGS Ores and Orogensis field trip to silver mines in Zacatecas, Mexico, led by Peter McGaw, found their way there from the Tucson symposium via a myriad of pathways. My friend Tom McCrory made a fairly straightforward trip by planes from Tucson to Dallas, Mexico City, and Zacatecas before grabbing a taxi for the last 30 miles to the field trip jumping off point in Fresnillo. Pity the poor woman from Kosovo who went from the meeting in Tucson to Zacatecas by a 22 hour bus ride.

Tom, whose Spanish is nearly as poor as mine, says that by the end of the trip, he could shout "Donde esta mi muletas!" ("Where are my bags!") with the best of them.  [He is third from the right in the back row, by the way]

Tom reports that, "The field trip went underground all three days they were there, including five hours in the largest producing silver mine in the world [note: in 2006, the Penoles' Proano (Fresnillo) mine produced 33.49 million oz Ag]  What the picture doesn't show is the incredible heat and humidity near the working faces.  In this mine they have intercepted five veins, the longest of which is 6.5 kilometers from east to west (typical precious metals ore shoots run less than one kilometer).  As most of the district is under alluvial cover, and has never been explored with modern methods, it is entirely possible it could hold more than 10 percent of the entire world reserves of silver."