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| Midas - Type Nevada Gold-Silver Deposits |
| GOLDSTORM, MIDAS TREND
DEPOSIT MODEL
EXPLORATION MODEL
PROPERTY DESCRIPTION |
NORTHERN NEVADA RIFTS METALLOGENIC TREND
Exploration Model:
The new, widely-accepted exploration model for the Midas, Sleeper, Ivanhoe, Mule Canyon, and Silver Cloud high-grade, vein-type, Low Sulfidation quartz-adularia gold-silver deposits in the Northern Nevada Rifts metallogenic province. These deposits were formed 14 to 17 Ma ago in extensional, rift-related felsic- or bimodal mafic-to-felsic volcanic environments. The top of the high-grade ore zones, e.g. at Midas, formed at boiling horizons 350 to 400 meters below the paleo- ground surface (new NEM fluid inclusion data), and extend downward for variable distances. The Midas Mine shows some of the world's best lateral vein ore continuity, with consistent head grades of 1.5 oz/ton Au and 12 oz/ton Ag, over a length of more than 1 kilometer, and this may be a characteristic of the Midas District which distinguishes it from lesser quality vein mineral districts in the Western U.S. The Midas Mine Au-Ag vein system has a vertical mineable extent of approximately 500 metres, and is up to 800 metres in height at Sleeper.
Mercury-rich but gold-poor silica sinter layers were formed at the ground surface above these high-grade deposits, along with local poddy discontinuous gold-rich shoots above -350 meters where zones of flash boiling extended upward along fracture-controlled fluid pipes, perhaps above an areal groundwater boiling interface. In the 1970s-1990’s, exploration companies typically only looked for near-surface (0 to –125 meters) open-pitable, disseminated gold-silver deposits. Silver Cloud, Ivanhoe Creek and others were never drilled, because they had no anomalous gold or pathfinder element geochem values (apart from Hg and Se) at the surface. Teck drilled a hole at Silver Cloud that contained 5 feet of 145 gpt Au in a silica veinlet-rich zone, at a depth of 318 meters, below barren surface sinters (see table below). Placer Dome leased the property from Teck, drilled 3 campaigns of holes in the past two years, and made a new discovery through drilling on the Egg Hill fault structure west of Silver Cloud's Teck discovery hole, returning 12.2 metres @5.6 gpt Au. The key to success in exploration for these Midas-type deposits is to conduct drilling into the zone of vein-metal continuity at 400+ metres below the paleosurface sinters, in structural dilation zones that have enriched mercury and/or selenium contents.
GOLDSTORM PROPERTY, Midas Trend, Elko County, NV
Staked; to be announced and described soon |
| Sugarloaf Property, Elko County |
SUGARLOAF GOLD-SILVER PROPERTY
RMIC GOLD and Sage Gold Inc. (SGX.V) control the SUGARLOAF gold-silver property, a Midas-type gold system, is located in the Edgemont Mining District of northern Elko County, south of Sheep Creek Reservoir, along trend to the north of the Cornucopia and Tuscarora Mining Districts. It has been optioned from RMIC Gold by Sage Gold Inc. (SAGE.V, www.sagegoldinc.com). It was formerly controlled by Newmont Mining Company, who in 1991 drilled at least one shallow angled RC hole on one of the Midas-type silica-pyrite vein systems on the property.
Location, Claim Status and Accessibility: The Sugarloaf property comprises thirty-two contiguous 20-acre lode claims located just south of Sugarloaf Hill in Sections 12,13, and 14 in T. 45N, R. 50E, and Section 18 in T. 45N, R. 51E, Elko County. No 3rd party claims are present in the area, and the mineral rights are controlled by the U.S. Bureau of Land Management. The surface rights are controlled in part by the Petan Ranch Company. The claims area is accessible year-round via good but unmaintained dirt ranch roads from Owyhee and Sheep Creek Reservoir 9 km to the northeast and from Highway 226 at Jack Creek to the south.
Targets at Sugarloaf: The 32 lode claims at Sugarloaf cover five high-level epithermal gold-silver targets in a large domal area of Eocene and Oligocene felsic volcanic strata. These strata are transected by widespread peripheral blanket silicification, limonitization and hematization, local vuggy quartz, and at least 2 areas with exposed high-level banded chalcedonic silica veining with local sulfide mineralization showing "pinhead" pyritic boxworks. Perhaps 100 metres of cover rock is believed to have been eroded from the original paleosurface at Sugarloaf, reducing the drill depths to ultimate target.
- 1) a N8dW-trending 3.65m wide high-level Midas-type limonitic silica vein system exposed, with pyritic boxworks, and highly anomalous values of As, Se, Te, and thallium. Newmont drilled a shallow RC hole (-62dN75dE, see figure) into this system, which intersected the target less than 100 metres below the present ground surface, returning highly limonitic to jarositic cuttings;
- 2) a NNW-trending 10+m wide limonitic, Gold enriched, Te-anomalous shear system, exposed in an open cut;
- 3) mineral systems within a large area showing strong silicification and sulfidation, with a NNW(?)-trending zone of strongly sulfidic banded chalcedonic silica veining, located near the core of the circular domal volcanic edifice;
- 4) NW to NNW-trending altered, limonitic to hematitic silicified strata with vuggy silica exposed; and
- 5) a N15W trending zone of argillized, limonite-hematite-vuggy silica altered felsic volcanic unit, possibly intruded by QFP porphyry dikes.
Geochemistry: Target areas #1 and #2 have exposed vein systems with high selenium and tellurium values that may be representative of a mineralized Midas-type system at relatively shallow depths (200-300 m below surface). Sample SC-1 by ACA Howe from Target #2 cut contained 110 ppb gold and elevated arsenic. Sample SL-3 showed a very high thallium value of 7.4 ppm Tl, which values could also be indicative of a gold system imprint. The Sugarloaf system is within the argillic alteration zone below the sinter model cap, which usually shows low gold values until the boiling zone is reached at depth. The Newmont drill hole(s) at Sugarloaf were too shallow to test the Midas-type targets predicted here.
Chemex Width Rock Types Gold Silver Hg As Se Te Bi / Tl
Sample (ppm) (ppm)
SC-1 5 m Tand;Si;arg;Lim .110 0.30 0.088 74 1.1
153352 5 m Tand:lim,Si,arg .003 0.17 0.20 106.5 7.0 1.53 15.85 Bi
153357 5 m Tand:lim,Si,arg .004 0.10 0.14 80.0 12.0 0.87 8.73 Bi
153372 10m Lim-goe cap .007 0.12 0.16 176.0 6.0 1.28 13.1 Bi
153368 3.7m Tectonic bx, 30%Si <.001 0.05 0.93 114 6.0 1.12 7.4 Tl
153379 2x7m Arg. lim volc bx <.005 <.02 1.07 51 12.0 1.01 10 Tl
153381 1 m Frac zone, vuggy qz <.005 <.02 .03 2 1.0 0.16 <10 Tl
Interpretation: The Sugarloaf system is now interpreted to represent a high-level Midas-type epithermal gold system of Miocene age, from which the top 100 meters (+/-) from the sinter paleosurface has been eroded. The Sugarloaf area shows a WNW-trending Mag high, cut by a Mag low where the vein systems are present. The area also reportedly shows a coincident Gravity high, which could be indicative of a porphyry-type intrusive stock in the area. Newmont held claims atop this area in 1991, and Anaconda drilled a molybdenum prospect a few miles from Sugarloaf in 1962. RMIC Gold believes that Sugarloaf, with the mineralized cuttings shown in the Newmont drillhole into Target #1, offers excellent potential to find a new gold-silver mine of economic size and grade. It is located in a very favorable, unpopulated area that is close to surface water and a potential workforce in the nearby town of Owyhee. A gravity survey and ground mag survey have been run by the optionee, and it is recommended that CSAMT and dipole-dipole IP surveys be conducted across the property prior to renewed drilling.
Please contact RMIC Gold or Sage Gold Inc. for more information. |
| Corridors Property, Elko County |
CORRIDORS PROPERTY, Ivanhoe District, Elko Co., Nevada
The prospective CORRIDORS gold-silver Property, comprising 62 lode claims, has been optioned from RMIC Gold by Sage Gold Inc. (SGX.V, www.sagegoldinc.com). Corridors is located northeast of Hecla-Great Basin Gold's high-grade Ivanhoe-Hollister gold-silver deposit and RMIC Gold's Ivanhoe Creek property. It was covered by Touchstone claims in the 1980s, but no drilling is known to have been conducted in the mineralized areas here. It is an interpreted nothern extension of the Ivanhoe Creek - Rimrock claims staked by RMIC Gold and optioned to Senator Minerals Inc.
Crosscutting banded chalcedony veins, hematite-cinnabar(?) silica flooding and structurally controlled argillic-FeOx alteration in fault-controlled hydrothermal breccias and volcanic flow rocks are present on these claims, which lie along two major NNE-trending fault corridors which extend SW to the Ivanhoe Creek property. The limited samples taken to date at Corridors, from the eastern 2 claimblocks (see Figure below) show anomalous gold, arsenic, selenium, and very high values of sulfur and tellurium. A highly mineralized area was just discovered in the southwestern claimblock, where hydrothermal breccias that are strongly argillized, hematitic, and contain crosscutting chalcedony veinlets and apparent cinnabar, occur in a parallel NE-trending fault corridor which may represent a radial fracture corridor cutting the outer ring of the Ivanhoe Creek collapsed dome field. No assays have yet been received from this area.
This highly prospective target area should be explored by rock and soil geochem sampling, gravity and CSAMT geophysical surveys, and subsequent drilling. Corridors is large enough to hold a Midas-size gold-silver mine.
TABLE 3. RMIC GEOCHEM COMPARISONS, CORRIDORS PROPERTY
ALSChemex
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Sample No.
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Location
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Rock Types
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Gold
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Silver
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Mercury Arsenic
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Selenium Tellurium
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Sulfur
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(ppm)
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(ppm)
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(ppm)
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(ppm)
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(%)
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10807
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Teck 4.5 opt drillhole
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“ “ chips tuff,opalite
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0.002
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<0.06
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0.25 3
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<1 <0.05
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0.31
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153384
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CORRIDORS-SW
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Hydr.BX, xc Si vns, hem-cinnabar
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0.002
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0.1
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5.2 21.9
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4.0 0.13
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4.87 |
153370
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CORRIDORS- SE
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Banded chalcedony in hem volcs
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0.001
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0.03
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10.3 31.8
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2 1.75
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5.52
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153371
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CORRIDORS- NE
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Banded chalcedony in hem volcs
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0.016
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0.08
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1.64 54.6
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3 1.89
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4.22
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| Hydrothermal Breccia at Corridors SW |
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