Mining - Seven Troughs district

Pershing County, Nevada, USA. Near the end of Stonehouse Canyon. Note that the tracks near the mouth have been buried by cave-ins! This area underwent a new flurry of activity around 1980, at the time of the last precious metal boom, and is undergoing another right now.

Seven Troughs district. This area is now a hotbed of new activity. There was a lot of drilling in fall 2012, and it may not be open to the public much longer.

With a somewhat more modern water pipe retrofitted! Seven Troughs district, Pershing County, Nevada, USA.

Seven Troughs district. You can tell this is an old one because it's just a piece of weathered log! Back in the 70s people would use pieces of plastic pipe, but those are now illegal due to some sort of deleterious effect on bird life. New claim markers are again wood, but they're machined-finished stakes from the lumber yard. This whole area was re-staked in fall 2010 by some group. I didn't ask the survey party who they were working for!

Seven Troughs District, Pershing County, Nevada, USA. "Tunnel Camp" got its name because it was the exit point of a long tunnel that drained the mines in the main part of the district. This looks like part of the mill site.

Usual 19th-century device for crushing ore. The stamps look like big pistons, with the wide end at the bottom being the "hammer" part. The big pulley on the side turned a shaft with cams on it, which would engage pawls on the shafts of the stamps. The cam would lift the stamp and then release it as it kept turning, so that the stamp dropped onto the ore. The stamps were set up to drop successively in a particular order so as to maximize the crushing effect. (This looks like a 5-stamp unit.) As you might imagine, stamp mills made a terrific racket, especially since they were usually run 24/7. They were rendered obsolete by such things as cone crushers, which are both less prone to jamming and yield a more consistent product.