Prior to 1979, the term 'millrock' was essentially unknown except to a few Canadian geologists. So, when a geologist from Conoco Minerals made a discovery of millrock with distinctive colloform massive sulfides and adjacent volcaniclastic breccias at the Itmay mine in the Huston Park area of the southern Sierra Madre, this was the starting gun for a rush to find minable copper, zinc, lead, gold, and silver. Soon, the Sierra Madre Mountains were filled with geologists searching for evidence of ancient black and white smokers, evidence of eruptive paleo-hot springs, and magnetic anomalies over magnetite-rich massive sulfide deposits. It didn't take long, but soon several volcanogenic massive sulfides were found, but a cat and mouse game was played between prospectors and geologists employing their mining rights on public land, and the card-carrying sierra-club forest service employees who did not like to see mining companies exercise these rights expressed in the 1872 Mining Law. So, every time a new discovery was legally made and claimed, the FS withdrew the area as well as access by using wilderness, roadless, etc. designations. Funny, they were never considered roadless or wilderness prior to the discoveries. Where a major base metal district existed, the FS stopped all, legal, access. So, if any politician tells you we are running out of resources - this is nothing more than an admission of their lack of understanding. There are billions (if not trillions) of tonnes of ore, not only in the Sierra Madre and Absaroka Mountains in Wyoming, but also in nearly every known mining district (past and present) in the world.
|Volcaniclastics at the Itmay mine in the Encampment |
district, Wyoming. These types of breccia are found
adjacent to rich millrock deposits.
|Colloform massive sulfide sample from the Itmay mine,|
Unfortunately, no one told them. The FS office in Laramie wanted to withdraw the entire Sierra Madre and Snowy Range from miners, even though their directive suggested they should be working for the public, rather than for their own biases. It appears that the Laramie office was filled with card-carrying Sierra Club members who were anti-mining, anti-logging, anti-people, etc, etc.
|Rich, copper-zinc-silver-gold gossaniferous highwall exposed at the United Verde mine, |
|Black smoker on exhibit at a museum |
|Steeply dipping, millrock photographed in the Ferris-Haggarty mine by the author.|
|Massive sulfide from the Kurtz-Chatterton vein|
Sierra Madre, Wyoming.
|Specularite-Chalcopyrite ore from the nearby Charter Oak mine at Puzzler Hill, Wyoming. This|
ore assay anomalous copper, gold and palladium
|Massive sphalerite ore (zinc-sulfide) from the Broadway |
prospect, Sierra Madre, Wyoming.