Mindora Mine, Garfield Mining District, Mineral County, Nevada, USAi

Regional Level Types
Mindora Mine	Mine
Garfield Mining District	Mining District
Mineral County	County
Nevada	State
USA	Country

Structure: Besides the major east-west shear, there are numerous, lesser north-south structures.

Commodity: Ore Materials: gold, molybdenite Gangue Materials: quartz

Deposit: The Garfield district is located within the Walker Lane, a north-northwest trending +300 mile long zone of Tertiary right lateral strike slip faulting. Large gold districts are near Mindora, notably the nearby Paradise Peak mine, and the Santa Fe district. Mineralization consists of 3 parallel veins extending NE and SW, and can be traced on the surface for more than 1,000 feet. The veins were located by crosscuts at various levels in the mountain. At the top level (level I) the vein is strongly brecciatd with iron staining and quartz, with a width of 4 to 10 feet. Level II has a crosscut of 575 feet with a drift of 800 feet and stoping of 400 feet. The third level has a crosscut of 415 feet with 200 feet of drifting. Some of the veins can be traced on the surface for over 1000 feet. At the Mindora property a section of Triassic and Jurassic sedimentary and volcanic rocks are exposed. The lower to mid Mesozoic rocks are intruded by late Cretaceous quartz monzonite dikes, and small plugs of Tertiary andesite and basalt. West of the property, the Mesozoic sequence is overlaid by Tertiary ash flow tuff and tuffaceous sediments. At Mindora, limestone of the Triassic Luning Formation has been re-crystallized, and extensively altered. The alteration at Mindora resembles the alteration in the Luning Formation in the Santa Fe deposit nine miles away to the northeast. The top -level vein is iron-stained quartz breccia. The other veins are not highly brecciated. A sample was taken from a brecciated vein near the main shaft and open stopes above a line of crosscutting adits to the east.

Deposit type: Epithermal vein, Comstock

Development: The Garfield district was originally discovered in 1882. A variety of deposits occur within the district. Gold, silver, lead and tungsten have been produced from quartz veins. Gold, silver, copper, and tungsten have been produced from skarn deposits. The total production from the district is unknown. In the 1980s a small junior resource company, Eureka Resources conducted exploration at Mindora. Eureka had two goals, to develop a reserve at Mindora, and find additional resources near the deposit. A series of short rotary holes successfully delineated a reserve of one million ounces, with grades of 0.037 opt gold, and 1.78 opt silver. The deposit is still open along strike to the west-southwest, and at depth. The reserve is essentially at the surface. A mine plan was developed by Eureka Resources, but a declining gold price in the 1990s prevented the project from going into production. In 1995 Eureka Resources was assessing the molybdenum potential of its Mindora property. It was worked in the early 1980s as a heap-leach, gold-silver operation. The property is also known to contain a potential resource of more than 50 million tons grading 0.11% molybdenum. Eureka Resources was considering drilling four 1,000-foot-deep holes to test the deposit. Subsequently the property was listed as owned by Century Gold LLC, and consisting of 18 unpatented mining claims that surround a one million ton reserve at defined by shallow drilling in the 1980s. Eureka Resources was restructured in 1998. The claims on Mindora property was subsequently allowed to lapse. In 2002, Nevada Sunrise LLC located 12 claims on the reserve at Mindora. The Nevada Sunrise claims left open the areas needed for infra-structure in the Eureka Resources mine plan, and the open projections of the Mindora deposit. Century Gold LLC located 18 claims to cover these extensions in early 2003. The size of the system is comparable to other systems that host large sedimentary rock hosted gold deposits. Mindora represents an under tested target with the potential to host multi-million ounce deposits.

Geology: The structure is an apparent laccolith, 2100 feet long and 1100 feet wide. Vertical exposure is around 500 feet. The mineralized area was intruded into a limestone.

Other Databases

Link to USGS MRDS:	10310367

References