I'm no geo but things don't look too bad after all........
"Geological setting of the Brasil, Huarato, XV, Callejon and the
Genova vein systems in the Acari – Cobrepampa Region, Southern
Peru
Perth, Australia: June 2
nd
, 2015 – The Directors of Minera Gold Ltd (“Minera Gold” or the “Company”)
(ASX:MIZ) are pleased to announce the results and findings from the first evaluation study completed on the wider
geological settings of the Brasil, Huarato, XV, Callejon and Genova vein systems, and its implication on the
potential for those concession to host large ore bodies containing copper, gold and silver mineralisation. These
concessions are 100% controlled by Minera Gold and located within a 25 km radius of the Company’s 100% San
Santiago copper-gold processing plant in Southern Peru.
Based on detailed mapping and systematic sampling of the Brasil vein system and the Callejon vein (previously
announced on the 29
th May and 1st June, 2015 respectively) and followed up by a first pass reconnaissance
geological study in the Huarato, XV and Genova concessions; the major findings are set out below:
In the XV concessions, the vein systems such as the San Juan vein, which extends over 800 m in length
and over 250 m in depth, is in the upper parts of a hydrothermal system at an elevation between 1840 m
and 1610 m above sea level. The potential of this system for copper mineralisation is within the
supergene blanket, enrichment and hypogene zones that could extend for 300 m or more at depth. Other
veins in the concession have been only mined less than 20 to 30 meters in the supergene blanket zone,
leaving the remaining ore insitu.
In the Genova concession which hosts the vein systems Chapi I, Chapi II and San Roque, which are at an
elevation of approximately 1,500 m, there is potential for this system to host copper mineralisation in the
supergene blanket, enrichment and hypogene zones that could extend for another 250 m or more at
depth. There is also potential to host gold mineralisation in the oxidised zone of the Chapi II vein.
In Brasil vein system, the reopening of historical shafts and tunnels that were closed by previous operators
is enabling our work to assess the full potential of the copper mineralisation in the enrichment and
hypogene zones. The reopening of the historical gallery and shafts that were driven to mine a parallel
vein to Brasil vein I suggests that there is more hypogene mineralisation at depth, as well as that the vein
remains open to the NW and SE.
In the Huarato concession, in the area known as Huarato Viejo, the opening of two new shafts and
exploration sublevels have identified ore shoots that are currently been assessed by the Company’s
geology, with detailed mapping and systematic sampling.
In the Callejon concession the continuation of the main ore shoot (30 m – 40 m in length by 1.5 m – 3 m in
width) is open at depth.
Detailed mapping and systematic sampling is been currently done at the XV concession main vein system known
as San Juan, Brasil recently reopened shafts and gallery, Huarato concession vein system at Huarato Viejo, and
the Genova Chapi I, II and San Roque veins. Announcements of these results will be made once certified results
are returned and interpreted.
This detailed work program, which will be followed up with a ground magnetic geophysics in the extended areas to
look for the extensions of the known vein system under cover, and IP studies over the existing veins (both on
surface and in the underground galleries) will allow the Company to identify the extension of the existing known
ore shoots and provide high priority drilling targets.
Mr Ashley Pattison, Managing Director of Minera Gold, commented “The maiden results of the reconnaissance
work within our wider Cobrepampa concessions provides a lot of encouraging information that will enable our
technical teams to prioritise their exploration programs in the short to medium term, The presence of so many
additional exploration targets certainly justifies the acquisition of the mining rights to this exciting concession
package.”
Minera Gold Limited
Introduction:
The vein systems of the Brasil, Huarato, Callejon, XV and Genova concessions are located in the productive
Acari-Cobrepampa region, which is within a 25 km radius of the Company’s 100% owned San Santiago coppergold
processing plant. Each of the vein systems are currently being evaluated on individual basis. Results for the
Brasil and Callejon systems have been previously announced in mid-March and also yesterday (see ASX
announcements dated on the 18th March, 28th May and 1st June 2015). This announcement reports the geological
settings of the vein systems across all of the concessions and its implication for hosting copper, silver and gold
mineralisation.
The Acari-Cobrepampa copper-gold-silver mining district is located in the much larger Marcona Iron OxideCopper-Gold
(IOCG) province, south-central Peru, about 550 km south of Lima. Although, a description of the
district regional geology was provided in the ASX announcement dated 18th March 2015, it is presented again in
this report for ease of reference.
Figure 1 and 2 (Appendix 2) show the location of the Cobrepampa mining district and the approximate location of
the Brasil concession. The Huarato, XV, Callejon and Genova concessions are all in close proximity to the Brasil
concession (Figure 3, Appendix 2).
The Marcona ICOG province hosts one of the biggest and largest concentrations of iron oxide in the central
Andes. Shougang Hierro Peru (Shougang Group subsidiary) operates the Marcona Mine that contains 1.4 Bton of
ore grading 55.4% Fe and uneconomic copper grades (average 0.12% Cu), in 8 open pits at 10 Mtons/year mining
operation (Figure 1 and 2, Appendix 2). Nanjingzhao Group owes the Pampa de Pongo project (Figure 1 and 2;
Appendix 2), the second biggest magnetite deposit, containing about 950 Mton grading 44%Fe, that is located
about 30 km to the southeast of Marcona mine. These iron rich IOCG deposits are thought to have been formed
in Middle Jurassic in a shallow marine environment along northeast striking fault systems that were active as a
major andesitic-dacitic volcanic activity took place.
In the same province, there is also the mid-Cretaceous IOCG copper-rich style mineralisation. The best known
project is the Mina Justa, located about 5 km northeast of the Marcona mine (Figure 1 and 2, Appendix 2). Mina
Justa is owned in a JV between Minsur SAC -70% (a Peruvian listed company) and 30% by KORES-LS Nikko
Copper Inc. The owners of the Mina Justa are currently completing a feasibility study on the project and the last
resource published indicated a JORC compliant indicated resource of 346.6 Mton grading 0.71% Cu, 3.8 g/t Ag
and 0.03 g/t Au at a cut-off grade of 0.3% Cu and inferred resources of 127.9 Mton at 0.6 % Cu.
Copper mineralisation at the large Mina Justa deposit occurs in hydrothermal breccia fillings and stockworks of
copper sulphide that is later than the deposition of magnetite lenses, within low angle faults that transgresses the
host volcanoclastic stratigraphy. A similar feature has been observed at Minera Gold’s 100% owned Tumi project
as reported to ASX on 19 July 2013, and some of the vein systems in the concessions that the Company leases.
In addition, there are more than 200 Cu-Ag-Au rich vein systems in the province in several districts, among them
the San Vicente-Trancas; Acari-Cobrepampa; La Loza and Machaynioc. The main vein systems in the
Cobrepampa-Cobrepampa district are La Argentina, Brasil, Purisma, San Juan, La Verde, Santa Rosa and Maria
del Carmen.
The IOCG copper-rich mineralisation systems in this area of Peru and further north (like the Raul Condestable
copper mine); and those IOCG copper-rich systems from Chile (e.g.: Candelaria, Punta del Cobre, Mantoverde,
etc), are all related with the emplacement of dioritic to monzo-granitic plutons during the mid-Cretaceous that
forms the Coastal Batholith, and extends along the coast of both countries.
The local geology in the Acari-Cobrepampa region consists of monzonite, monzogranites and granodiorites cut by
aplitic dykes. In some areas, these rocks have intruded Jurassic andesite and dacite volcanic rocks or
volcanoclastic sediments. Outcrops of monzonite, monzodiorite, granodiorite and granite are also observed. All the
outcrops are mostly overlain by rhyodacitic pyroclastic sediments, eluvium and alluvial sand and conglomerate
deposits for the majority of the area of interest.
Tenements Location, Ownership and Concession Holder
Figure 3 shows all the concessions in the Acari – Cobrepampa area that are 100% owned by Minera Gold’s
subsidiaries, and those under mining lease agreements. The area is located approximately 57 km inland from the
Pan American Highway (km 555) at an altitude of between 1,200 m – 2,000 m asl. Access is by a paved road to
the town of Acari (22 km), and from there to the town of Otapara (17 km), where the San Santiago plant is located,
is by a consolidated road. The distance from the plant to the various concessions varies between 15 and 25 km
on dirt service roads. The concession package comprises approximately 6,380 hectares.
Minera Gold Limited
Table 1 provides the details of the concession names, the registration codes, hectares and the name of the
companies which hold contracts of mining lease agreements with the concession owners, as well the San
Santiago plant.
Minera Gold, is 100% owner of Derivados y Concentrados SAC, Korisumaq SAC, Grupo Cobrepampa SAC and
Compania Minera Cobrepampa SAC. These group companies have in place mining lease agreements until
August 2023 with Insumos Mineros Fenix SAC, Grupo Minero Fenix SAC and Grupo Minero Pampacolca SAC.
They are all private Peruvian mining companies. The mining lease agreements provide the sole right for Minera
Gold to explore and mine within the concessions and also establish a royalty payment commitment of 7% on the
concentrates produced at the San Santiago Plant from these concessions, less transport and ore treatment costs.
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