The Belen Cu-Au porphyry is located 19 km east from the township of Tingo Maria in central
Highlights:
First outcrop recognition of a linked porphyry copper-gold and epithermal gold mineral system at Belen within an 8 km by 2 km trend (Figures 2-4) across three prospect areas (
Detailed field work has been ongoing at the Belen prospect, which represents a small proportion (4%) of Hannan's total landholding at the Valiente project. Hannan has six geologists and support team working full time on the project. Field work has focused on detailed mapping, channel and systematic soil sampling to cover the entire 8 km intrusive trend at the Belen porphyry target (Figure 1). Soil sampling to date covers about 50% of the 8 km Belen trend on a grid spacing of 100 m x 100 m. A total of 1,630 samples have been taken.
The Company has also completed a successful 4,880 line km aeromagnetic survey across all of its 100% owned mining concessions at Valiente. Results from this survey will be provided post processing in the coming month.
Field work has identified a leached copper-gold porphyry coincident with soil anomalies, with well-developed quartz veining at upper topographic levels and evidence for an enriched chalcocite blanket sampled over 1 km within lower lying creeks at the Ricardo Herrera Copper-Gold Porphyry Target.
Detailed 1:2,500 mapping has revealed an early hornblende feldspar porphyry of andesitic composition with phyllic alteration, intermediate argillic alteration, relics of potassic alteration with veins of early biotite (EB), M-type and A-type.
The alteration zone extends for 850 m x 250 m within a broad footprint of a copper anomalous and altered zone of intermineral hornblende feldspar porphyry stock of andesitic composition that extends over 1,600 m x 800 m (Figure 2).
A detailed pole-dipole induced polarization geophysical survey over the Ricardo Herrera target is planned in the coming month and the initial stages of drill permitting are being undertaken.
Vista Alegre
A 1.8 km long gold-bearing epithermal target area identified by large gold mineralized boulders of quartz-pyrite and iron oxides as well as strongly gold anomalous soil samples has been discovered 2.5 km NW of
Sortilegio
Earlier stage work (soil sampling and prospecting) at the Sortilegio porphyry target have indicated the presence of a second copper-gold porphyry at Belen located 7 km northwest of
The Belen prospect, 100% owned and explored by
Ricardo Herrera Copper-Gold Porphyry Target
A linked porphyry copper-gold and epithermal gold mineral system has been identified at Belen within an 8 km by 2 km trend (Figures 2-4). Recent detailed field work has identified a leached copper-gold porphyry with well-developed quartz veining at upper topographic levels and evidence for an enriched chalcocite blanket sampled over 1 km within lower lying creeks at the Ricardo Herrera Copper-Gold Porphyry Target. This coincides with a highly anomalous Cu-Au-Mo soil anomaly, initially reported here, over a 1,600 m by 800 m area above a mapped and radiometrically dated Miocene-age porphyry intrusion.
The Ricardo Herrera porphyry stock was intruded in several stages, broadly termed early, intermineral, and late, all interpreted within a relatively short time interval. The early stages are hornblende feldspar porphyries of andesitic composition, whereas the late stages consist of unaltered feldspar porphyries of andesitic composition. The intrusions caused contact metamorphism and hydrothermal alteration that partially obliterated the original texture and composition of the sedimentary country rocks. Two early porphyries are identified. The first being an intermediate argillic (chlorite from secondary biotite-white micas) with relicts of potassic alteration (secondary biotite-magnetite) with 'EB' type veinlets (early biotite), M-type (magnetite) veinlets and few A-type veinlets (quartz). The second early porphyry intrusion is characterized by A-type veinlets, jarosite-goethite iron oxide veinlets with phyllic alteration (quartz-white sericite), argillic alteration (kaolinite). The intermineral stock is dominated by supergene argillic alteration and propylitic alteration (chlorite, epidote).
In porphyry copper systems, the area with the highest copper grade often corresponds to the early porphyries. The focus of the detailed geological mapping has therefore been to identify this area and to sample it with systematic rock sampling. Assays from this work are pending.
At Ricardo Herrera the combined early hornblende feldspar porphyry is at least covering an area of 850 m x 250 m on the surface. But limited exposures, that are mostly constrained to creeks and rare outcrops, make it difficult to define the true area. Observed copper minerals include pyrite, chalcopyrite, chalcocite, molybdenite, neotocite and chrysocolla mineralization. The intermineral hornblende feldspar porphyry contains supergene argillic alteration and minor neotocite. Moderate to pervasive secondary biotite alteration is common throughout the host rock. Strong chloritization and pyritization is observed replacing the secondary biotite.
At this initial stage of exploration at the Ricardo Herrera porphyry target, the early porphyry occupies a surface area of 0.21 km2 which is comparable to the 22.37 Moz gold La Colosa deposit in
Channel sampling at Ricardo Herrera has been focused on creeks where outcrop exposures are good. In many places access is a limiting factor of what can be sampled. Most channels have to date been taken from zones peripheral to what is interpreted to be the core of the system (Figure 3). The results are summarized in Table 1. Results from 34 individual channels include 5 m @ 0.11% Cu and 5 ppm Mo. This channel is open to either side and is from the strongly leached and weathered exposure of the early diorite porphyry. Fractures are rich in jarosite and goethite after pyrite and chalcopyrite (Figure 3). Importantly, the best and highest-grade results have been achieved from the leached early porphyry. The results are also low in manganese therefore interpreted to be representative of a leached porphyry system. Channel sampling continues.
Vista Alegre Epithermal gold target
Vista Alegre consists of a gold-bearing epithermal target identified by large gold mineralized boulders of quartz-pyrite and iron oxides. Strongly gold anomalous soil samples have been discovered 2.5 km NW of
Previous work has also included:
Systematic 100 m x 100 m soil sampling program. Two strong gold anomalous trends that extend for 1,800 m and 970 m respectively have been identified. Assays have been received to date from 376 samples covering an area of 2 km x 1.7 km. Values range from 0.1 ppm Au have been sampled over a trend of 1.6 km that is parallel to the main gold anomaly. A total 43 rock samples from boulders average 0.48 g/t Au, 6 g/t Te and range from below detection limit to 2.69 g/t Au and
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