Guayacan Target


The region is dominated by a structurally prepared area of linear, north-south, magnetic low features and an extensive circular magnetic response as defined by our 2011 airborne magnetic survey at 200 metre line spacing.

Three old hand-mining workings have been discovered where subcrop and outcrop form resistant ridges of biotite-granodiorite, granite intrusive bodies and felsic dykes.

Conventional soil geochemical sampling along 13 grid lines was conducted as a case history response study over the three historic mineralized areas which are separated along a 2.5 kilometre north-south linear trend. Since much of the region is covered by alluvial sand and gravels with little to no subcropping, a 36-line grid of Soil Gas Hydrocarbon (SGH) geochemical survey sampling also covered the known mineralization and anomalous magnetic response patterns over a 3.5 kilometer North to South grid.

Conventional soil geochemical data indicates an anomalous response for Cu, Mo, Ag and Au associated with old prospector workings and show an extensive 2.5 kilometre long linear trend between the three mineralized showings.

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Soil Gas Hydocarbon (SGH) geochemistry results were interpreted by Activation Laboratories Ltd. for the approximate 4 km X 2 km survey (1,074 samples). The data confirms the location of conventional soil geochemical survey anomalies but significantly expands the area of copper and gold SGH anomalous patterns in the survey area. A small SGH survey conducted at the eastern skarn zone discovery area also resulted in SGH anomalous gold and copper response patterns.

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The conventional soil and SGH geochemical sampling over the grid area shows anomalous patterns which can be directly related to the known trend of mineralized subcrop but also expands the target area. The scale of the target is suggestive of porphyry and related skarn mineralization.


The Guayacan target area has been prospected and sampled during 1:10,000 scale geologic mapping of the El Cobre property. The area is generally a flat plain where weathered down granodiorite and andesitic rocks are intruded by granite and felsic dykes associated with structures. Young volcanic rocks are capping exposures to the north and east of the known target. 

The 2015 work program to date has consisted of prospecting and field geology. Previous exploration by the Company at Guayacan has included a helicopter airborne VTEM-MAG geophysical survey, an extensive soil geochemical survey (710 samples), a soil gas hydrocarbon geochemical survey (1074 SGH samples), and geological mapping and prospecting, all systematically completed during the 2011 - 2014 seasons. The exploration programs have followed-up on anomalous circular and linear magnetic low features obtained from the airborne VTEM-MAG geophysical helicopter survey. The recent positive results have expanded the number, and defined in more detail, zones of alteration and surface mineralization in subcrop-outcrop across the 3.5 kilometer wide expression of the airborne circular magnetic geophysical anomalous patterns. New discoveries included zones peripheral to precious metal bearing porphyry systems, skarns, unroofed porphyry system veins, stockworks and breccia vein mineralization.

The Guayacan target is situated in flat lying Sonora ranch lands with thin young volcanic cover rocks or sand and gravel material overlying much of the bedrock geophysical anomalies expression. The significant ASTER IMAGERY patterns coincident with the disrupted airborne magnetic survey response of circular features and super-imposed linear magnetic lows have been mapped as epithermal and porphyry --style alteration. This is interpreted by the Company as the expression of multiple phase intrusive events related to this largely unroofed mineralized porphyry system.

A detailed update on the multiple high grade gold and silver targets and gold-copper porphyry system mineralization found to date across the Guayacan porphyry system is reported in News Release WMR 15-2.

Guayacan North

The Guayacan North "Mine" area is characterized by a small hand-works decline and several small dump piles of mineralized material including quartz-hematite vein, felsic dyke and also the host coarse-grained, equigranular granitic body. Biotite, sericite, magnetite and epidote and intense red hematite alteration are present as alteration features. Faulting and dyke emplacement are evident plus leaching and oxidation of fractures and contacts.

Four composite and grab samples contained gold, specifically 17,260 ppb, 12,143 ppb, 17,930 ppb and 16,367 ppb, with an approximate 1:1 Ag:Au ratio. These samples were also high in mercury, arsenic, bismuth and lead while copper contents varied between 824 ppm to greater than 1% copper. It is this type of mineralized material consisting of abundant red iron oxides, minor copper as malachite, azurite and chrysocolla which was then processed for gold extraction by "arrastre" methods by the local prospector who rediscovered the "lost mine" and sold it to Westminster Resources Ltd. (100% owner).

Red hematite alteration and iron oxide "boxwork textures" indicate that sulphide leaching has occurred at surface. This weathering may have removed much of the copper contents while leaving less mobile elements such as molybdenum, silver and gold behind at surface. See the coincident copper, gold, silver and molybdenum conventional soil geochemical responses at the three old prospects on the four geochemical grid maps.

Guayacan Middle

The best result from the Guayacan Middle target is a composite of grab samples from quartz-hematite subcropping grading: 

0.905% Copper
1.1% Lead
0.29% Zinc
80.0 g/t Silver
13.5 g/t Gold
1495 ppm Molybdenum
6.6% Iron
100 ppm Antimony
135 ppm Bismuth
13140 ppb Mercury
551 ppm Vanadium
>100 ppm Tungsten

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The large scale of the circular magnetic features suggests possible association with porphyry system alteration and intrusive body emplacement. These magnetic features are coincident with the extensive multi-element soil geochemical anomalous patterns will be further explored over the 4 km X 2 km grid by 3D-IP geophysical surveying. Geologic mapping suggests intrusive body emplacement along structures. The more circular patterns observed in the magnetic map may be interpreted as variable magnetic response to the multiple intrusive phases and degrees of magnetic destruction by porphyry system hydrothermal and magmatic fluid alteration.

Guayacan South

The best sample from the old workings shaft outcrop is a grab sample of mixed hematite-quartz breccia and quartz vein in cuprous granite which graded:

2.46% Copper
463.3 ppm Lead
391.0 ppm Zinc
126 g/t Silver
675.5 ppb Gold
147.1 ppm Arsenic
5.35% Iron
61.17 ppm Bismuth
11.08 ppm Tellurium
238 ppB Mercury

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This target's anomalous soil geochemical results suggest that the area on trend to the South of the old shaft is highly prospective and warranting 3D-IP geophysical surveying.

Guayacan East

The best grab sample is from quartz vein material at epidote-magnetite skarn subcrop area which graded:

0.167% Copper
2.52% Lead
0.12% Zinc
26.0 g/t Silver
6.05 g/t Gold
897 ppm Arsenic
8.23% Iron
129.7 ppm Antimony
268.2 ppm Bismuth
4364 ppm Vanadium
679 ppb Mercury

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The Guayacan East target is located peripheral to the eastern portion of the circular magnetic anomalous patterns. SGH geochemical soil survey case history short grid lines tested the known mineralized SGH response zone. The positive SGH response warrants detailed follow up.

Cautionary Note

Geochemical results for rock samples collected on the property are from single "grab", "composite grab" or "chip" samples where their collection is irregular to randomly spaced based upon the geologist's or technician's judgement. The sampling is conducted during regional and reconnaissance exploration where sub-cropping and outcropping rock material can be used to evaluate the mineral potential of an area. The geochemical data derived from these types of samples (grabs, etc.) cannot be relied upon to be representative of the grade of mineralization.

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