Monday, January 18, 2016

Yerington Monday: The Mines of Lyon County: Malachite Mine and Mason Valley Mine

Yerington Monday: The Mines of Lyon County: Malachite Mine and Mason Valley Mine

As a YHS graduate, I never knew that our yearbook was named after the Malachite Mine.  If you live long enough, one finds out all kinds of interesting things.


The Yerington Mining District is located in Lyon County, Nevada. Copper was found in the Yerington District very early in history of Nevada, in 1865. A number of copper veins were mined around Yerington. Many of these mines were of a type called skarn, in which hot fluids from a granitic type rock change limestones into ore. Often skarns contain very interesting minerals. In the Yerington area, skarns are found with garnet and epidote. Copper in these mines is found in the mineral chalcopyrite.

Until 1940, the district produced over 17 million dollars, chiefly in copper. However, a very large and important copper mining company, Anaconda, began exploring the granitic rocks next to the town of Yerington. In 1953, Anaconda produced copper at its mill in the town of Weed Heights, adjacent to Yerington. Between 1953 and 1965, Anaconda produced 803,224,674 pounds of copper, worth $255,154,480. The Yerington pit is now idle, filling with water. But another copper mining company, Arimetco, is operating the MacArthur pit, a few miles north of Yerington. The town of Yerington has been a ranching and farming center, as well as a mining town. It never depended entirely on copper mining, and it never became a ghost town.

In 1894, the town of Yerington, Nevada, was established near the Walker River in Mason Valley in the east-central portion of Lyon County, Nevada. Before being named for Henry Marvin Yerington, superintendent of the former Virginia and Truckee (V&T) Railroad, this community had been known by several other names including Greenfield, Willow Switch, Pizen Switch, and originally Poison. The initial name originated in recognition of a saloon owned by a Mr. Downey, who manufactured his own unique brand of liquor from frequently questionable ingredients. In 1894, community leaders wanted to attract a spur of the Virginia & Truckee Railroad and changed the name of the town again, this time to honor Henry Marvin Yerington, the railroad's superintendent.N


Stock Certificate, issued/uncanceled  1910's




The Malachite mine is from a third to half a mile south of the Mason Valley mine and is on the same general zone of mineralization. The worldings comprise some old adits from which was taken partly oxidized ore similar to that of the Mason Valley mine. At the time of visit a shaft was being put down in the limestone below the old tunnels, but this shaft was not yet in ore and was not examined.


Malachite copper ore


Malachite mine


Malachite mine


Malachite and Mason Valley mine map




MASON VALLEY MINE. The Mason Valley mine is three-quarters of a mile southeast of the Bluestone and at nearly the same elevation. The ore body outcrops at about 5,500 feet above sea level, and has been cut by tunnels running southwestward into the ridge at elevations of 5,385, 5,325, and THE YERINGTON COPPER DISTRICT, NEVADA. 109 5,200 feet.

A new tunnel, known as No. 4, is being driven at 5,080 feet, and is expected to enter the ore at about 1,100 feet from the portal. There are also .some abandoned workings, which attained a ' depth of nearly 200 feet, and which, like the Bluestone mine, supplied copper sulphate to the mills on the Comstock lode. The recent work is of an exploratory character, and is mainly on the No. 3 level. The country rock of the ore is limestone, which.shows much local alteration. This rock is cut off just north of the mine by the fault previously mentioned, which has dropped the Tertiary volcanic rocks against it. Whether the limestone is entirely continuous along the west side of this fault with that of the Bluestone mine, or whether some exposures of schist intervene, was not ascertained. The limestone area continues to the south over the spur between the Mason Valley and Malachite mines, both of these being on the same irregular zone of mineralization. Some schist, however, separates this belt from the limestone of the McConnell mine. (See fig. 6.)


Mason Valley Mine

No comments:

Post a Comment

Related Posts Plugin for WordPress, Blogger...