The Wall Street Gold Mill is a very interesting and rare example of a complete small desert gold mill. And to boot, it is only a short walk inside the backcountry of Joshua Tree National Park.
Once owned by renown prospector and rancher Bill Keys, this mill was a custom mill, meaning that it processed ore in batches for many local area mines. Keys started up the mill here in 1932 after purchasing the stamps from New Eldorado Company at Pinyon Well and relocating it from there. The mill had been working at Pinyon Well since 1891. Keys worked the mill intermittently until 1942 when WWII closed all the gold mines. His son took over and operated it for a brief time starting in 1949. Bill last ran the mill for about a month in 1966. It was acquired by the National Park Service in 1971 from the Keys estate.
As a side note, Bill also shot a man named Worth
We have visited the mill a few times over the years. Even walking out there at night once. It is a great place.