slgwv's photos with the keyword: stamp mill

Ore crushing device, in which cams on a turning shaft raised and then dropped piston-like hammers, the "stamps", onto ore. They were notorious for making a tremendous racket, particularly since they tended to run 24/7. This one processed ore from the Golden Gate mine in extreme eastern California (not by the actual Golden Gate!), which was brought down by a tramway. The mine was active in the early 20th century--a bit late for stamp mills, which by then were being displaced by newer technology like cone crushers. This mill has been the object of some attempts at preservation: it's been stabilized by the cables attached to the posts in front, and has also had a lot of debris cleared off. Inserts are (1) an interpretive plaque, courtesy of E Clampus Vitus; (2) a close-up of the stamps; (3) a close-up of one stamp hopper, showing the manufacturer's name, based in San Francisco(!); and (4) the pulley in the middle of the camshaft. (3) and (4) are on the areas magnified.

On the camshaft between the 5-stamp banks on either side. Golden Gate stamp mill, California

Golden Gate stamp mill, showing one of the hoppers where the stamps stamped. The manufacturer's label reads, "Joshua Hendy Iron Works S.F. Cal." Yes, in the early 20th century there was heavy industry in San Francisco!

Golden Gate stamp mill. A ten-stamp unit--five on either side of the middle pulley!

Courtesy of E Clampus Vitus. We'll pay no attention to the fact that the writer confused "illusive" with "elusive"!

Tonopah Mining Museum, Nevada. A 19th century device for crushing ore--a belt turned the big pulley, which in turn spun a camshaft that lifted and dropped the stamps. Altho stamp mills lingered into the 20th century at small undercapitalized mines, they were obsolete even by Tonopah's heyday after the turn of the last century. I think, therefore, this mill was brought in for the museum and was never used locally.

Aurora, Mineral County, Nevada, USA. Note the wheel for turning the camshaft to lift the stamps in the foreground. See adjacent photo for a description of Aurora.

Pigeon Spring, Palmetto district, Nevada, USA. The only wooden part that still survives is the frame for the stamps. The heyday of this district was around the turn of the last century.

Pine Grove, Nevada, USA. Now missing the stamps!

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.

Obviously a 5-stamp unit! Bodie, California, USA. Bodie was about the first gold-mining camp in the western US to electrify, and to adopt the cyanide process, both in the mid 1890s.