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Genesis, Blue Star, Beast, SOLD, Bobcat, Deep Star, North Star, Lantern, Exodus
Nevada, USA
Main commodities: Au Ag


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The Blue Star / Genesis mine and associated Beast, North Star, Bobcat, Deep Star, Lantern, Exodus and SOLD deposits are located in northern Eureka county, north-eastern Nevada, USA. They are some 36 km to the NNW of the township of Carlin. These deposits lies on the northern tip of the Lynn Window, approximately 6 km to the north-west of the Carlin mine.

Published reserve and production figures Blue Star/Genesis and adjacent deposits are as follows:

      68 Mt @ 1.1 g/t Au = 75 t Au  (Proven+probable reserve, 31 Dec. 1992, Christensen, 1993)
      34 Mt @ 1.42 g/t Au = 48 t Au   (Genesis, total geological reserve, 27 Dec. 1989, McFarlane, 1991)
     ~31 Mt @ 3 g/t Au = 93 t Au   (Genesis, pre-mining resource, Jory, 2002)
     ~3.6 Mt @ 2 g/t Au = 7.8 t Au   (West Genesis, pre-mining resource, Jory, 2002)
      1.45 Mt @ 4.11 g/t = 5.9 t Au Au   (Initial Reserve at Blue Star, 1968 - Paul, et al., 1993)
      0.7 Mt @ 4 g/t Au = 2.8 t Au   (Remaining Reserve at Blue Star, 1986 - Zimmerman, 1987)
      22 Mt @ 0.95 g/t Au = 21 t Au   (Blue Star, total geological reserve, 27 Dec. 1989, McFarlane, 1991)
     ~3.6 Mt @ 2 g/t Au = 7.8 t Au   (West Genesis, pre-mining resource, Jory, 2002)
     ~9.3 Mt @ 0.6 g/t Au = 5.6 t Au   (Blue Star Ridge, pre-mining resource, Jory, 2002)
     ~10.3 Mt @ 1.2 g/t Au = 12.5 t Au   (Blue Star, pre-mining resource, Jory, 2002)
     Blue Star has been mined since 1974, Genesis since 1986
      5.2 Mt @ 1.2 g/t Au = 6.2 t Au (North Star, proven+probable reserve, 1992, Christensen, 1993)
      7 Mt @ 1.64 g/t Au = 11.5 t Au   (North Star, Total geological reserve, 1989, McFarlane, 1991)
     ~3 Mt @ 2.4 g/t Au = 7 t Au   (North Star, pre-mining resource, Jory, 2002)
     ~1.5 Mt @ 0.6 g/t Au = 0.9 t Au   (SOLD, pre-mining resource, Jory, 2002)
      7.3 Mt @ 0.7 g/t Au = 5 t Au   (Beast, production+reserve, 2000 - Resser, et al., 2000)
     ~2.5 Mt @ 0.6 g/t Au = 1.5 t Au   (Beast, pre-mining resource, Jory, 2002)
     ~7.5 Mt @ 0.9 g/t Au = 6.8 t Au   (Bobcat, pre-mining resource, Jory, 2002)
      18 Mt @ 0.89 g/t Au = 16 t Au   (Bobcat, Total geological reserve, 27 Dec. 1989, McFarlane, 1991)
     ~1.75 Mt @ 30 g/t Au = 53 t Au   (Deep Star, pre-mining resource, Jory, 2002)
      0.77 Mt @ 32 g/t Au = 24 t Au   (Deep Star, proven+probable reserve, 1992, Christensen, 1993)
      15.7 Mt @ 0.89 g/t Au = 14 t Au   (Lantern, Total geological reserve, 1989, McFarlane, 1991)
      1.6 Mt @ 14 g/t Au = 22 t Au   (Lantern, reserve1993, Andrew, 1993)
     ~3 Mt @ 1 g/t Au = 3 t Au   (North Lantern, pre-mining resource, Jory, 2002)
     ~5 Mt @ 1.2 g/t Au = 6 t Au   (South Lantern, pre-mining resource, Jory, 2002)
     ~4 Mt @ 3.1 g/t Au = 12.4 t Au   (Exodus, pre-mining resource, Jory, 2002)

The 1992 reserve figures include the Genesis, Blue Star, Beast and SOLD deposits. Genesis and Blue Star are part of a larger, interconnected hydrothermal system which embraces North Star, Bobcat, Genesis, Blue Star, Beast and SOLD. These deposits are distributed over a distance of around 3.5 km in a NNW direction along the Carlin Trend and a width of up to 2 km (Paul, et al., 1993). The Lantern deposit lies between the Carlin and Blue Star/Genesis mines, while the Post/Goldstrike orebodies are less than 2.5 km to the north of Blue Star/Genesis.

These deposits are operated as the North Area of the Carlin operation.

The first indication of mineralisation at Blue Star was the discovery of turquoise by a barber from the town of Carlin in 1925. The site was re-discovered in 1929 and the mining of turquoise commenced with open pit and shallow underground workings. The mine changed hands several times to 1954 with the total estimated turquoise production over the period being in excess of $US 1.4 m. Gold was first recognised at the workings in 1957. In early 1961, following a rash of option and lease transactions, the property was drilled and an intersection of 3 m @ 13.5 g/t Au obtained from a percussion hole. Channel sampling from some of the deeper turquoise workings assayed up to 20 g/t over 1.5 m widths. A 200 tpd cyanide mill was constructed from second hand equipment from nearby mining locations and in 1961 a small operation commenced. However due to metallurgical problems only 25 kg of gold were produced. Several large mining companies declined the offer of taking an interest in the property at that stage. John Livermore of Newmont visited the property in 1961 and recommended that his company assess its potential. After a 3 week campaign of detailed mapping and sampling a mineable reserve of 0.5 Mt @ 4.5 to 6 g/t Au was estimated, with a recommendation to acquire the property. Negotiations however, were not successful (Paul, et al., 1993).

The Blue Star property was eventually acquired by Newmont in 1968. Drilling delineated a reserve of 1.45 Mt @ 4.1 g/t Au. Mining commenced in 1974, based on this reserve, and closed in 1984 with 0.7 Mt @ 4 g/t Au remaining. In 1984 the Genesis deposit was discovered to the north-east of Blue Star by rock chip sampling and drilling. Accelerated drilling in the South Main ore zone at Genesis was prompted by a shortage of available mill grade ore in the district at that stage to feed the Carlin #1 mill. Mining began in this zone in 1986 prior to the full Genesis deposit being outlined. In 1989, after a 5 year shut down of the Blue Star mine, the main Blue Star/Genesis operation was commenced, resulting in the development of a single project open pit. The current mining rate of 155 000 tpd will remove the remaining ore at an overall stripping ratio of 3.5:1 waste:ore (Paul, etal., 1993). Ore above 2 g/t Au is milled, while that between 0.2 and 2 g/t is heap leached (Andrew, 1993). The final dimensions of the Genesis/Blue Star pit is planned to be 1800 x 1000 m by 400 m deep (Paul, et al., 1993).

The Blue Star/Genesis Mine is owned and operated by the Newmont Gold Company (1996).

Geology

The primary geologic features of the Blue Star/Genesis mine and environs are:  i). an autochthonous sequence of Ordovician to Devonian carbonates of the Eastern Assemblage which are  ii). overlain across the thrust contact of the eastward directed Roberts Mountains Thrust by  iii). the allochthonous Ordovician silici-clastics of the Western Assemblage. A transitional silici-clastic sequence, the Rodeo Creek Unit occurs adjacent to the thrust surface, above the carbonates. The overall sequence is exposed in the crest of a NNW trending, north plunging antiformal structure along the Tuscarora Spur, a ridge which has been separated by a 'Basin and Range' basin from the main Tuscarora Mountains to the east. This antiformal structure is assumed to be a faulted segment of the regional Tuscarora Antiform. The sediments are cut by the east-west trending, steep walled, Jurassic Goldstrike Stock which separates the Blue Star/Genesis deposit from the Post/Goldstrike orebody to the north. These rocks are overlain by Tertiary air-fall and water-lain tuffs and Quaternary alluvials (Paul, et al., 1993)

The succession within the immediate mine area is as follows, from the structurally lowest:

Devonian, Popovich Formation, which is locally characterised by three subdivisions,
* Lower unit, 150 to 200 m thick - composed mainly of light to dark grey, micritic limestones which are often fossiliferous. It is thin to mostly medium bedded, with some thick bedded horizons. Interbedded, thin bedded silty, platy limestone is also present, often brecciated and silicified (Paul, et al., 1993).
 * Middle unit, 120 to 180 m thick - the lower unit grades upwards into a thin-bedded, thinly laminated, platy, silty limestone with interlayered medium bedded limestone which is mostly decalcified. This unit has been predominantly altered to a diopside calc-silicate hornfels in the mine area (Paul, et al., 1993).
 * Upper unit, 100 to 180 m thick - dominantly a light to dark grey, sandy textured micrite, interbedded with thinly bedded silty limestone. At Genesis the upper 50 m is often de-calcified into a siltstone. It is locally sheared, brecciated, argillised and silicified and commonly contains sheared lenses of carbon rich clay (Paul, et al., 1993).
At Blue Star the Popovich Formation contains turbiditic channelised sandstones up to 30 m thick, while at Genesis a sequence of lenticular sedimentary breccias and turbiditic facies rocks are proximal to the gradational contact between micritic and silty limestones (Jordan, 1991).
Devonian, Rodeo Creek Unit, 90 to 180 m thick - conformably overlies the Popovich Formation and is characterised by black to dark grey, thinly bedded siltstone, carbonaceous mudstone and argillite. Local interbeds of tan to dark grey calcarenite occur near the base of the unit, and light grey, medium bedded calcareous siltstones are found higher in the sequence. Adjacent to the Goldstrike intrusive the siliceous portions of the unit are commonly altered to quartz hornfels while the calcareous sections have been modified to calc-silicate hornfels. The base of the unit is marked by a 5 to 15 m thick massive, thick bedded calcarenite and may contain up to 40% detrital quartz sand. In the mine area this calcarenite is intensely silicified and forms prominent outcrops making it an obvious marker horizon (Paul, et al., 1993).
The Rodeo Creek unit typically weathers to a rust-brown to tan colour and forms slopes. It is locally absent in the western part of the Genesis deposit due to Antler age thrusting (Paul, etal., 1993).
Roberts Mountains Thrust - a major thrust surface initially accommodating eastward directed over thrusting of the Western Assemblage silici-clastics onto the Eastern Assemblage carbonates during the Devono-Carboniferous (Paul, et al., 1993).
Ordovician, Vinini Formation, 300 to 1500 m thick - this unit represents the allochthonous Western Assemblage of silici-clastics above the Roberts Mountains Thrust. The formation is typically a medium grey to tan, medium to thin bedded, laminated, siltstone and chert. It weathers to rust brown and forms subdued exposures. Local interbeds of calcareous siltstone are metamorphosed to calc-silicate hornfels while the siliceous sediments are modified to quartz-hornfels (Paul, et al., 1993).
This succession is cut by three distinct intrusives, as follows:
Jurassic, Goldstrike Stock, 158 Ma in age - within the Blue Star/Genesis mine area this stock is essentially a fine to medium grained diorite to granodiorite. It is commonly propylitically altered and may contain abundant disseminated pyrite (Paul, et al., 1993).
Tertiary, Biotite-feldspar Porphyry, 28.3±0.7 Ma - This intrusive is generally present a series of dykes that are 1 to 10 m thick and are characterised by 1 to 2 mm biotite phenocrysts with subordinate feldspar phenocrysts. These dykes are commonly altered and appear as bleached kaolinite-clay masses with opalescent sericite flakes (Paul, et al., 1993; Jordan, 1991).
Lamprophyre Dykes, of uncertain age - occurring as 1 to 1.5 m thick dykes that contain hornblende, biotite and feldspar (Paul, et al., 1993).
Unconformably overlying all of the above rocks is the:
Tertiary, Carlin Formation, 0 to 30 m thick - characterised by tan to white, thinly bedded, laminated, water lain lacustrine tuffs with local channel gravels. The base of the formation is characterised by a poorly sorted conglomerate (Paul, et al., 1993).

Structure

Blue Star and Genesis occur within a north-westerly trending antiformal structure on the Tuscarora Spur Horst, separated from the main Tuscarora Mountains to the east by a Basin and Range basin. The antiform, as observed in the south wall of the Genesis Pit, may be associated with a compressional event, the exact age of which has not been determined, but appears to be pre-ore (Paul, etal., 1993). It plunges to the north at 10°. The western limb dips at 30° to 40° to the west, while the east limb dips east at 65° to 70° and has been displaced by the north-west trending Gen Fault. The Blue Star deposit is on part of the western limb of the same antiform. This limb has been folded synformally and cut by steeply dipping normal faults. This synform has a parallel trend to the antiform and also plunges to the north-west (Jordan, 1991).

At least six phases of deformation are recognised in the northern Lynn Window, as follows:

Palaeozoic Thrusting - related to the Devono-Carboniferous Antler Orogeny. The main representative of this phase is the Roberts Mountains Thrust which places the Vinini Formation over the Rodeo Creek Unit and the Popovich Formation. In the east wall of the Genesis Pit, numerous low angle faults associated with this thrusting have been mapped in the upper plate Vinini Formation (Paul, etal., 1993). Within the narrow north-west extension of the Lynn Window the Roberts Mountains Thrust has an undulatory surface with dips ranging from flat lying to greater than 50°. Within the Blue Star mine the thrust exhibits vertical relief differences of more than 150 m. The mineralisation in the old 'south' and 'east' pits at Blue Star are below the thrust, while that of the north pit is directly above the structure (Zimmerman, 1987).

Post Goldstrike Stock Thrusting - cross-cutting relationships indicate that a second thrusting event post dates the emplacement of the Goldstrike Stock. Numerous small scale, moderately west dipping structures cross-cut calc-silicate hornfels attributed to the stock in the southern section of the Genesis Pit. In addition, the West Genesis ore zone is associated with low angle structures that can be traced westward through the Goldstrike Stock (Paul, et al., 1993).

North-South High Angle Faulting - which may be observed on the western edge of both Genesis and Blue Star. In this area the west dipping Ridge Fault has an apparent reverse off-set of the order of 200 m. However, south of Blue Star this same fault dips east, and as such has a normal offset. This fault cross-cuts both sets of thrusts, but is cut by all other high angle sets. In the hanging wall of this fault, the apparent reverse displacement has brought the low angle structural zone of the West Genesis ore zone closer to the surface where it is known as the Bobcat deposit. Highly differing grades of mineralisation on opposite sides of the Ridge Fault indicate that it is probably a pre-mineralisation structure (Paul, et al., 1993).

North-west High Angle Faulting - occurs as a prominent set of faults in the Blue Star district and is observed in the west Genesis area as the Reindeer and No. 9 faults. These WSW dipping faults generally have normal movement with a step fault pattern to the south-west. Blast hole assays indicate that this fault set provides some structural control on mineralisation (Paul, et al., 1993).

North-east High Angle Faulting - resulted in the prominent fault set of the K-Fault zone which trend at 35° to 45° and dip 50° to 60° NW. These are a series of sub-parallel shears that are commonly intruded by biotite-feldspar porphyry dykes. This fault set occurs elsewhere in the district and predominantly cross-cuts the north-west striking set. Mineralisation appears to have a strong structural control in and adjacent to the K-Fault zone, with the highest grade being where it is cut off by the Gen Fault (Jordan, 1991; Paul, et al., 1993).

Basin and Range High Angle Faulting - representing the final structural phase in the district. The most prominent feature in the district is the Gen Fault, a north-west striking, steeply dipping normal fault. Displacement of the Popovich Formation indicates at least 250 m of vertical movement. Mineralised gravel clasts in the Tertiary Carlin Formation which is offset by the Gen Fault indicates that the mineralisation is pre Basin and Range.

Alteration

A variety of alteration or rock modification styles are recognised at Blue Star and Genesis, as follows:

Contact Metamorphism - associated with the Goldstrike Stock which produced both siliceous and calc-silicate hornfels. These rocks have been described in the literature as 'skarns'. However, based on the mineralogy they appear to be hornfels. The calc-silicate hornfels are derived from the carbonate facies of both the Popovich and Vinini Formations. The dominant assemblage in these comprises diopside, quartz, calcite and montmorillonite with lesser garnet, tremolite and wollastonite. The quartz-hornfels arise from metamorphism of the silici-clastic units. Propylitisation is indicated by the development of calcite, chlorite and pyrite which are generally restricted to the Goldstrike Stock (Paul, etal., 1993). Although ore occurs within the hornfelsed sediments, the hornfels on the margins of the Goldstrike stock are barren (Andrew, 1993).

Silicification - is the most common alteration type and is observed as quartz veins and veinlets which frequently coalesce into pervasive flooding in ore zones. This quartz flooding in the orebody commonly exceeds 70% quartz (Paul, etal., 1993). Silicification is commonly associated with gold mineralisation. In a 1988 study, Newmont showed that the highest gold values at Genesis were in the areas of highest silicification. Silicification textures vary widely and include massive chert-like, saccharoidal and miarolitic (Jordan, 1991).

Argillisation - semi-quantitative analysis data indicate that argillisation occurred throughout the orebody. Kaolinite which is the dominant clay, comprising up to 25% of the rock, is concentrated in the upper portion of the Genesis deposit. Montmorillonite has been replaced by the kaolinite, although minor amounts of montmorillonite, illite and sericite are still present. At Blue Star the clay is more commonly enriched in gold (Paul, etal., 1993, Jordan, 1991). Sub-micron sized gold is found within the lattices of montmorillonite and kaolinite. This clay alteration exhibits weak to strong limonite with lesser amounts of Cu and Fe-As oxides. Clays along fractures and joints in relatively un-altered limestone also contains gold (Zimmerman, 1987).

Decalcification (or de-carbonatisation) - is seldom observed in the carbonates of the orebody at Genesis. Decalcification textures are most common in the west side of Genesis, near the top of the Popovich Formation, where less intense contact metamorphism is obvious (Paul, etal., 1993). In contrast Jordan (1991) states that "a large portion of the Palaeozoic sediments have been decalcified by hydrothermal solutions. Decalcification created pore space leaving the rock receptive to gold bearing hydrothermal solutions".

Pyritisation - is apparently intimately associated with hypogene gold mineralisation. Two types of pyrite are observed,  1). coarse grained brassy coloured pyrite that is barren of gold, and  2). a later generation of very fine grained, dark grey pyrite that may contain gold in its crystal lattice. This second type is also typically rich in arsenic (Paul, etal., 1993). Gold occurs in this type of pyrite, in the outer rims of the grains with associated As and Sb (Andrew, 1993).

Supergene influences - a large proportion of the Genesis deposit has undergone supergene and possibly hypogene oxidation. Oxidation is nearly complete in the upper parts of the West and Main Genesis ore zones. At depth oxidation is controlled by faults, joints and bedding planes. Common by-products of arsenian-pyrite are jarosite and scorodite (Paul, etal., 1993). Oxidation is recorded to depths of 200 m (Jordan, 1991).

The contact metamorphic hornfels development appears to be geometrically related to the Goldstrike Stock, while the decalcification, argillisation and silicification are spatially linked to the gold mineralisation (Paul, et al., 1993). It might be suspected that a lot of the argillisation was associated with supergene processes.

Mineralisation

Gold mineralisation within the Genesis Pit occurs as two distinct zones,  i). the Main Zone - which is restricted to the footwall of the Gen Fault zone, proximal to the intersection of the K-Fault. The K-Fault generally strikes at 30° with an associated 330° to 340° trending 'structural zone' that has been offset by the Gen Fault. Mineralisation in this zone is found almost exclusively in hydrothermally altered metamorphic rocks of the Popovich Formation along low and high angle structures (Paul, etal., 1993); and  ii). the West Zone - which is also localised within the Popovich Formation on the western limb of the Tuscarora Spur Antiform and is contained within a low angle fault zone. This low angle reverse fault has been connected by drilling with the Bobcat and North Star mineralisation to the west (Paul, et al., 1993). The mineralised hosts in this zone have not been metamorphosed to hornfels. Higher grades occur along NW and NE structures and in the siltier units of the Popovich Formation. These latter lithologies are though to have been decalcified silty limestones (Jordan, 1991).

Within the Blue Star Pit gold mineralisation is found within three structural zones, the 'east', 'south' and 'north'. In the 'south' and 'east' zones a number of west to north-west anastomosing high angle faults produced a zone where intense hydrothermal argillisation took place. In these the host rock is limestone. Gold occurs in the lattice of montmorillonite and kaolinite clays that principally occur along fractures and joints in relatively un-altered limestone. The intersection in the old Blue Star 'south pit' and in NNE trending normal faults that continue into the 'north pit', are the focus of very high gold grades of up to 200 g/t Au in 6 m blast hole composites, with visible mm sized gold.

Jordan (1991) refers to the 'West Ore Zone' being located within variably calcareous siltstones, mudstones and argillites of the Rodeo Creek Unit. This zone, he adds, is lensoidal, stratigraphically controlled and trends at 10° with a 35° dip to the west. It is assumed that this reference, which is included separately to the Genesis and Blue Star paragraphs, refers to the Bobcat and North Star deposits. These are the western continuations of the Genesis West Zone to the west of the Ridge Fault.

The Deep Star mineralisation is located to the north of Genesis. The first hole into the ore returned an intersection of 107 m @ 26.6 g/t Au (Ryneer, 1991).

Gold is present in the Genesis deposit as sub-micron sized particles. It occurs primarily in association with  1). limonitic clays in NW to NE trending fractures, faults and joints in the silicified and well indurated rocks;  2). argillisation along bedding planes in the siltstones and argillites; and  3). to a lesser degree, with pervasive silicification and quartz veins in all lithologies. Gold mineralisation occurs sporadically within the strongly kaolinised biotite-feldspar porphyry, especially where they are cut by faults and shear zones (Zimmerman, 1987). Payable ore is generally indicated by limonite staining (Andrew, 1993).

Within the un-oxidised ore, gold occurs in the crystal lattices of a later generation of very fine grained, dark grey pyrite that may contain gold in its crystal lattice (see the 'Pyritisation' paragraph in the 'Alteration' section above). This second type is also typically rich in arsenic (Paul, etal., 1993). Gold occurs in this type of pyrite in the outer rims of the grains with associated As and Sb (Andrew, 1993).

Run of mine 'mill grade ore' is approximately 3 g/t Au, with a cut-off of around 2 g/t Au for that ore type. The West Ore Zone at Genesis is generally leach grade. In the deep ore zone one refractory shoot contains 6 g/t Au (Andrew, 1993).

Surface rock chip and soil geochemistry over the Genesis South and Main zones, where the ore was exposed at surface, were anomalous in As, Sb and Hg. Geochemical assays of drill samples indicate an As halo of +1000 ppm that extends outwards from the gold mineralisation. Sb values of +100 ppm are restricted to the orebody. Hg does not correlate directly with Au, although concentrations of 1 to 30 ppm occur within and adjacent to Au mineralisation (Paul, etal., 1993). Typical geochemical values in the orebody area at Genesis are 750 to 2000 ppm As, with peaks of 8000 ppm As; 75 to 130 ppm Sb, with similar peaks of up to 8000 ppm Sb. Tl values may be 1 to 2 ppm, with peaks of up to 18 ppm Tl. Peak Hg values may reach 140 ppm (Andrew, 1993).

Beast is unique in that among the Carlin type Au deposits it has as much as 50% of its ore hosted by a 37.3 Ma porphyritic rhyolite dyke.   However, despite this it is said to have all of the characteristics of Carlin style mineralisation, namely  i). an ore assemblage of fine pyrite, arsenian pyrite and arsenopyrite,  ii). an association of Au with As, Sb, Hg and Tl and high Au/Ag ratios,  iii). a paragenesis that includes early Fe-As sulphides and kaolinite , intermediate stibnite and late barite,  iv). moderate to strong silicification and/or kaolinisation of rocks in ore zones and decarbonatisation of silty carbonate rocks adjacent to faults.   It is less than 1 km from the Genesis deposit, 3 km from Post-Betze and other important deposits, all of which are located along the same Post-Genesis Fault.   The host rhyolite helps put an age constraint on the mineralisation.   Strong leaching of the rhyolite has led to an altered rock composed of quartz and kaolinite with gold concentrated in matrix- and clast-supported siliceous breccia developed in and near the faulted footwall of the rhyolite dyke adjacent to Siluro-Devonian silty carbonate, but also occurs in massive quartz-kaolinite in rhyolite and limestone. Supergene alunite is dated at 18.6 Ma (Ressel, et al., 2000).

For detail consult the reference(s) listed below.

The most recent source geological information used to prepare this decription was dated: 2002.     Record last updated: 23/10/2014
This description is a summary from published sources, the chief of which are listed below.
© Copyright Porter GeoConsultancy Pty Ltd.   Unauthorised copying, reproduction, storage or dissemination prohibited.


  References & Additional Information
   Selected References:
Drews-Armitage S P, Romberger S B, Whitney C G  1996 - Clay alteration and Gold deposition in the genesis and Blue Star deposits, Eureka County, Nevada: in    Econ. Geol.   v91 pp 1383-1393
Heitt D G, Dunbar W W, Thompson T B, Jackson R G  2003 - Geology and geochemistry of the Deep Star gold deposit, Carlin Trend, Nevada: in    Econ. Geol.   v98 pp 1107-1135
Ressel M W, Noble D C, Henry C D, Trudel W S  2000 - Dike-hosted ores of the Beast deposit and the importance of Eocene magmatism in Gold mineralization of the Carlin Trend, Nevada: in    Econ. Geol.   v95 pp 1417-1444
Zimmerman C  1987 - Geology of the Bluestar gold deposit: in Johnson J L (Ed.), 1987 Bulk Mineable Precious Metal Deposits of the Western United States - Guidebook for Field Trips Geol. Soc. Nevada    pp 280-282


Porter GeoConsultancy Pty Ltd (PorterGeo) provides access to this database at no charge.   It is largely based on scientific papers and reports in the public domain, and was current when the sources consulted were published.   While PorterGeo endeavour to ensure the information was accurate at the time of compilation and subsequent updating, PorterGeo, its employees and servants:   i). do not warrant, or make any representation regarding the use, or results of the use of the information contained herein as to its correctness, accuracy, currency, or otherwise; and   ii). expressly disclaim all liability or responsibility to any person using the information or conclusions contained herein.

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