Boarder Gold Mine
Site Name Boarder Mine A.K.A. Boarder Gold
Commodity: Gold (Major) Silver (Minor) Copper (Minor)
Location: Esmeralda County, Nevada
Primary: "Boarder Gold Deposit"
District: Goldfield District:
Land Ownership: BLM Administrative Area
Administrative Organization: Tonopah District BLM
Owner Name: Aurum Exploration, Inc.
Info Year: 2013
Record Type: Site
Operation Category: Past Producer
Deposit Type: silicified zones at shear intersections
Operation Type: Surface-Underground
Year First Production: 1904
Year Last Production: > 1970
Discovery Year: 1901
Years of Production: 1904-1970s
Deposit Size: M
Model Name: Epithermal quartz-alunite Au
Form: Irregular to tabular or knobby
Description: The Boarder Mine Deposit is located to the west of the ring fracture zone that controls the main Goldfield deposits.
Description: Tertiary deposits are domed and faulted by steeply dipping post Miocene: N-S and E-W faults.
Alteration Type: L
Alteration Text: Large envelopes of intense argillic alteration surround most of the ore zones with silicification of core ore zones.
Age Type: Host Rock
Age in Years:
Age Young: Oligocene
Commodity Comment Ore Materials: gold
Commodity Comment Gangue Materials: quartz, alunite, barite, gypsum, limonite, kaolin
Economic Factors Comment Historic recorded production from the main Goldfield district is 4,190,133 ounces of gold at an average 0.541 oz/ton gold, including about 160,800 ounces of gold from reworked tailings. 1996 reserves of the Gemfield area were reported at 9.5 million tons of ore grading 0.04 opt Au.for a total of about 500,000 ounces of gold. In 2006, Metallic Ventures Gold Inc. announced recent in-fill drill results and reported a resource for the Gemfield Project of 9,500,000 tons of material grading 0.040 ounces of gold per ton.
Geology Comment The Goldfield mining district is located at the site of a complex and long-lived igneous intrusive and volcanic center that is defined by eruptive vents and curviplanar faults. The local volcanic stratigraphy, a moderately well-defined ring-fracture zone, concentric structural doming, high sulfidation-style quartz-alunite hydrothermal alteration, and widespread copper-gold mineralization are all genetically related to the emplacement of a large dominantly andesitic igneous complex and the most significant components of which are late Oligocene to early Miocene in age..
Workings Comment Older workings were predominantly underground with later surface workings.