Delamar Mine

Mine Description

NOTE: a request was made to note that the current owner is United Delamar Mine.

Site Name

Primary: Delamar Mine
Secondary: Lucky Bar Claim
Secondary: Jim Crow Claim
Secondary: Monitor Claim
Secondary: Monitor No. 2 Claim
Secondary: Hog Pen Claim
Secondary: Gold Cup Claim

---

Commodity

Primary: Gold
Primary: Silver
Tertiary: Copper
Tertiary: Iron

---

Location

State: Nevada
County: Lincoln
District: Delamar (Ferguson) District

---

Land Status

Land ownership: Private
Note: the land ownership field only identifies whether the area the mine is in is generally on public lands like Forest Service or BLM land, or if it is in an area that is generally private property. It does not definitively identify property status, nor does it indicate claim status or whether an area is open to prospecting. Always respect private property.

---

Holdings

Not available

---

Workings

Not available

---

Ownership

Owner Name: Beta Minerals
Info Year: 2005

---

Production

Not available

---

Deposit

Record Type: Site
Operation Category: Producer
Deposit Type: vein; breccia filling
Operation Type: Surface-Underground
Year First Production: 1890
Year Last Production: 1930
Discovery Year: 1891
Years of Production:
Organization:
Significant: Y
Deposit Size: L

---

Physiography

Not available

---

Mineral Deposit Model

Model Name: Epithermal vein, Comstock

---

Orebody

Form: tabular

---

Structure

Type: R
Description: The dominant structural feature in the region is the Caliente caldera complex, an east-elongated (50X22 mi; 80X35 km) complex of inset calderas in Nevada and Utah. It spans an age of at least 10 million years (23-13 Ma), an unusually long activity period for a caldera complex. It is bounded on its northern and southern sides by transverse zones, which are east-striking late Mesozoic to Cenozoic structures that cross the Great Basin and accommodate different amounts, types, and rates of crustal extension to the north and south. The Caliente complex was highly extended along transverse zones and faults that were synchronous with caldera magmatism. One of these is the Timpahute transverse zone, along the northern side of the caldera complex.

Type: L
Description: Rocks in the Delamar District are cut by abundant normal faults.

---

Alterations

Not available

---

Rocks

Role: Associated
Age Type: Associated Rock Unit
Age Young: Miocene

Name: Basalt
Role: Associated
Description: dikes
Age Type: Associated Rock
Age Young: Tertiary

Name: Rhyolite
Role: Associated
Description: dikes
Age Type: Associated Rock
Age Young: Tertiary

Name: Quartzite
Role: Host
Age Type: Host Rock
Age Young: Early Cambrian
Age Old: Neoproterozoic

---

Analytical Data

Not available

---

Materials

Ore: Gold
Ore: Tetrahedrite
Ore: Chalcopyrite
Ore: Bornite
Ore: Chalcocite
Ore: Malachite
Ore: Chrysocolla
Gangue: Pyrite
Gangue: Quartz

---

Comments

Comment (Development): The first ore in the district was discovered by a group of Italian miners headed by John Vietti working on a lease. The Lucky Bar claim was located by John Roeder, the Goldcup claim by Joe Conway, John Roeder and Cap Garden. Captain DeLaMar purchased claims in 1893 and began the active development that made the Delamar district Nevada's biggest gold producer in the period from 1895 through 1900. The Delamar mines shut down in 1909. The mine operated intermittently under the Bambergers from 1902 until 1932. In 1931, the Caliente Cyaniding Co. was preparing to treat tailings from the Delamar mill. The Jack Berry lease on the Lucky Bar (Hog Pen) claim produced considerable shipping ore. Beginning in about 1982 the district saw renewed exploration by a series of joint ventures, including work by Homestake, FMC Gold Company, Hanna Mining, Aur Resources, and Phelps Dodge Mining Company. Exploration was not confined to the immediate vicinity of the old Delamar Mine but was also focused on the Easter prospect about five miles east-northeast of the Delamar Mine. More than 100 drill holes were completed on the prospect, and Homestake Mining Company made a resource estimate in 1988 of 4 million tons at 0.056 oz/ton at a 0.02 oz/ton cutoff (224,740 oz Au), based upon results from 25 drill holes. Fischer-Watt Corp. explored the property in 2001. Beta Minerals became active in the Delamar District in 2003 with a drilling project 5 miles to the northeast at the historic Easter(n) (Taylor) Mine. Beta located 135 mining claims covering 1129 hectares on the western flank of the Delamar Caldera in the Delamar District, Beta's claims contain the extensions of the former producing Delamar vein systems including the Delamar, Magnolia, Jumbo and April Fool veins. In addition to the high-grade underground vein targets on the western half of the Delamar properties, Beta geologists have defined two areas of strong hydrothermal alteration associated with anomalous gold, silver and trace element concentrations on the eastern side of the properties. This mineralization is exposed in a north-trending 300-m wide zone of faulting, which can be traced for 1225 m on the surface. This shear zone is the outer ring fracture zone of the Delamar volcanic caldera formed along the western edge of the collapse structure. The exploration target on the Ring Fracture Zone is a disseminated gold deposit amenable to open pit methods similar to the prolific Round Mountain Mine. In the 2004 field season, Beta geologists conducted geological mapping, rock chip sampling, and completed two soil sampling grids totaling approximately 82 hectares in area, defining several geochemical anomalies associated with strong hydrothermal alteration and quartz-adularia veining. The company will conduct detailed mapping and sampling on the anomalous areas, and evaluate the potential for geophysical definition of drilling targets along the mineralized zones in 2005.

Comment (Economic Factors): The Delamar district has produced approximately 650,000 ounces of gold since its discovery in 1892, and was Nevada's largest gold producer in 1900. The Delamar Mine was the main producer of the district , with a total production through 1933 of $12,854,600. The Delamar Mine reportedly produced 217,000 unces of gold and 420,000 ounces of silver. Remaining reserves of the Delamar Mine in 1988 were reported to be 200,000 tons of ore grading 0.079 ounces of gold per ton. Reserve figures after that were combined with those for the Easter project.

Comment (Geology): The faults and magmas of the Caliente area belong to two episodes, first the middle Cenozoic pre-Basin-Range episode of calc-alkaline magmatism and northeast- and northwest-striking oblique-slip faults, folowed by the Basin-Range episode of bimodal magmatism and north-striking normal faults. Gold deposits that surround the caldera complex are interpreted to represent leaching, transport, and deposition of metals by ground water moving through the transverse zones and heated to boiling by intracaldera magmas. The Delamar gold district is situated on the southwestern side of the caldera complex, where these processes took place.In addition to the high-grade underground vein targets on the western half of the Delamar properties, Beta geologists have defined two areas of strong hydrothermal alteration associated with anomalous gold, silver and trace element concentrations on the eastern side of the properties. This mineralization is exposed in a north-trending 300-m wide zone of faulting, which can be traced for 1225 m on the surface. This shear zone is the outer ring fracture zone of the Delamar volcanic caldera formed along the western edge of the collapse structure. The exploration target on the Ring Fracture Zone is a disseminated gold deposit amenable to open pit methods similar to the prolific Round Mountain Mine. Rocks in the mine area consist of a thick section of tilted and faulted Cambrian quartzite. Sediments are tilted 35 degrees to the southeast; volcanics show less tilting. Sediments show some effects of contact metamorphism. Tertiary basalt dikes and sills, and post ore lamprophyre dikes are present. Tertiary east-west- trending rhyolite dikes post ore. Major deposits of the district were hosted in the oldest rocks, the Early Cambian Prospect Mountain Quartzite. Other deposits are in volcanic breccia, intruded by rhyolite dikes as at the Magnolia Mine, and in several of the limestone units.

Comment (Location): The mine is located on the west flank of the Delamar Mountains, on the ridge above the town of Delamar.

Comment (Workings): Most of the extensive historic underground workings are now inaccessible. There were originally 16 levels of underground workings at the Delamar Mine and a large glory hole.

Comment (Commodity): Ore Materials: native gold, tetrahedrite, chalcopyrite, bornite, chalcocite, malachite, chrysocolla, a telluride (?)

Comment (Commodity): Gangue Materials: pyrite, quartz, iron oxides, manganese oxides

Comment (Deposit): Ore is found in the Delamar or Monitor vein, which extends for a strike-length of 2700 feet. The vein is composed of 5 main ore shoots each of which is of variable thickness up to up to 300 feet. Material of all grades found in the shoots; grade decreased rapidly below level 10. The ore consists chiefly of breccia cemented by chalcedonic quartz. Mineralization is also found in chalcedonic quartz veins and along bedding planes and fractures. Most ore was oxidized, with a reddish or greenish tint. Only the Hog Pen ore shoot contained free gold. The ore reserves identified by Homestake and World Wide Minerals in the 1980s are within a 1,600-foot-long by 40- to 90- foot-wide segment of the Main Vein, part of a 7,000- foot-long mineralized structure. The Delamar ore bodies included epithermal veins in sedimentary rocks as well as bedding replacement ores in limestone. Gold values ranged up to several ounces per ton on some veins, but the majority of the gold production came from a large underground block cave operation known as the Delamar Glory Hole, where a large tonnage of mill grade ore was mined. The Glory Hole orebody is located at a structural intersection between north-trending gold-bearing veins with east-west trending faults intruded by volcanic dikes radial to the Delamar Caldera. Beta's claims cover relatively untested, similar structural intersections buried under recent sediments to the north and east of the former producer.

---

References

Reference (Deposit): Rowley, Peter D. and others, 2001, Field trip to the Caliente Caldera Complex, east-striking transverse zones, and nearby mining districts in Nevada-Utah; implications for petroleum, ground-water, and mineral resources; in The geologic transition, high plateaus to Great Basin; a symposium and field guide; the Mackin volume, editor, Erskine, M. C. and others Guidebook - Pacific Section, American Association of Petroleum Geologists, vol.78, pp.401-418, 2001.

Reference (Deposit): Beta Minerals website: www.betaminerals.com

Reference (Deposit): Snee, Lawrence W. and Rowley, Peter D. , 2000, New 40Ar/39Ar dates from the Caliente caldera complex, Nevada-Utah; at least 10 million years of Tertiary volcanism in one of the world's largest caldera complexes; Abstracts with Programs - Geological Society of America, vol.32, no.7, pp.461.

Reference (Deposit): Lincoln, F. C., 1923, Mining Districts and Mineral Resources of Nevada: Nevada Newsletter Pub Co; Reno, NV.

Reference (Deposit): Smith, A.M. and Carpenter, J., 1931, Notes on Inspection Trip; NBMG Mining District File 167, item 3.

Reference (Deposit): NBMG Mining District File 167, items 6 and 7, Potential National Historical Register Site Report.

Reference (Deposit): Godbe, W.S., 1894, Eng. & Min. Jour., vol. 57, p. 106.

Reference (Deposit): Bentz, J.and Smith, P., 1983, NBMG Field Examination Report, Sept 30,1983.

Reference (Deposit): Barton, Harlan N. and Day, Gordon W. 1984, Reconnaissance geochemistry of the Delamar Mountains; Bureau of Land Management Wilderness Study Area (NV 050-0177), Lincoln County, Nevada. U. S. Geological Survey, Open-File Report OF 84-0360, 49 pp.

Reference (Deposit): Long, K.R., DeYoung, J.H., Jr., and Ludington, S.D., 1998, Database of significant deposits of gold, silver, copper, lead, and zinc in the United States; Part A, Database description and analysis; part B, Digital database: U.S. Geological Survey Open-File Report 98-206, 33 p., one 3.5 inch diskette.

Reference (Deposit): Callaghan, E., 1937, Geology of the Delmar District, Lincoln Co, Nev. Nevada Bur. of Mines vol . 31, no. 5, p. 50-58.

Reference (Deposit): Tschanz, C.M. and Pampeyan, .H., 1970, Geology and Mineral Deposits of Lincoln Co. Nev. Nev. Bur. Mines Bull. 73, p. 141.

Reference (Deposit): Emmons, S F, 1901, The Delamar and Hornsilver Mines: 2 Types of Ore Deposits in Utah and Nevada: AIME Trans, vol 31, p. 658-683.

---

Nevada Gold

Nevada has a total of 368 distinct gold districts. Of the of those, just 36 are major producers with production and/or reserves of over 1,000,000 ounces, 49 have production and/or reserves of over 100,000 ounces, with the rest having less than 100,000 ounces. Read more: Gold Districts of Nevada.