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Mazar-Ashu South Area

MAZAR-ASHU SOUTH and MAZAR-ASHU NORTH

INTRODUCTION

Prospecting in the field seasons 2013-2015 was focused on the Mazar-Ashu North area, and in the 2016-2019 seasons on the Mazar-Ashu South area.

During the first three seasons, it became obvious that both targets belong to one structure and are divided into two areas by physical boundary only, that is, the ridge.

The geochemical difference between the two zones reflects just geochemical zoning. So, Mazar-Ashu North specializing more in gold rather than copper, but Mazar-Ashu South vice versa.

Before 2014-2015 Mazar-Ashu South (mineralized part) has never been tested due to the glaciation. That’s why the history of this occurrence is fascinating in that it was only discovered in 2014, primarily due to the retreating ice from the local glacier exposing copper mineralization, which was seen initially as talus material and in hard rocks only in 2016. Although during the Soviet era, this area would have been investigated, the permanent ice cover, difficult terrain, and hostile climate prevented discovery until now.

As such, Mazar-Ashu South is fairly unique in Central Asia in that the vast majority of occurrences and deposits that we know of today were originally discovered in the Soviet era. Therefore, Mazarashu South represents a new discovery but is at a fairly basic stage of knowledge at this time.

In any case, Mazar-Ashu North and Mazar-Ashu South is definitely one structure and its length is about 13-14 km, and width from 1.5 km to 3.0 km and Mazar-Ashu South is most likely the center of the porphyry system, and that is why we have focused our efforts on this mineralized area lately. We believe that some 580 million tons of ore, i.e. 4 600 thousand tons of copper and 116 tons of gold, are embedded in the Mazar-Ashu South core part and our findings are based on the information introduced below.

MAZAR-ASHU SOUTH

GEOLOGY & MINERALIZATION

Although the regional picture for this part of the Tien Shan is reasonably well understood, the local scale geology of the Mazar-Ashu area is somewhat less well known.

Notwithstanding this, our team has put together a geological map for the license area based on the regional understanding coupled with few seasons of fieldwork. The results of this work are shown below:

Geological Map of Mazar-Ashu Area

From an observational standpoint, the area can be seen as a sequence of Proterozoic metasedimentary rocks that are cut by later intrusives. These include granites, granodiorites, diorites (including their porphyry phases), granosyenites, as well as intrusion breccias. Some examples of these are shown below:

Photo of Host Rocks

In terms of mineralization, considerable evidence of surface copper mineralization is evident comprising malachite and azurite staining both from vein-type mineralization as well as of a more disseminated nature. In addition, primary sulfidic material was also seen in the float, typically as massive chalcopyrite, bornite, and pyrite. A selection of mineralized specimens is shown below:

Photo of Feldspathic Veins. Stockwork

Above 4,000 m, a well-pronounced stockwork is developed with a dominant vein direction of east-west, dipping sub-vertically to the south. From observations, this can be seen extending up the cliffs to the west for hundreds of meters and is open at both ends and to an unknown depth.

Photo of Feldspathic Veins. Stockwork

Above 4,000 m, a well-pronounced stockwork is developed with a dominant vein direction of east-west, dipping sub-vertically to the south. From observations, this can be seen extending up the cliffs to the west for hundreds of meters and is open at both ends and to an unknown depth.

Photo of Stockwork Mineralization (Dog for Scale)

Photo of Stockwork Mineralization in Detail

In addition to the stockwork zone, several other areas of surface copper mineralization have been identified (malachite staining is noticeable in much of the scree debris on the walk up to the stockwork). For example, in about 800 m to the south another mineralization so-called “Malakhitovaya” Zone The zone is exposed in the rock with an average slope angle of about 30 degrees. Therefore, it was sampled with the assistance of climbers. The zone is shown below:

Photo of Malakhitovaya Zone (climber for scale)

2016 EXPLORATION RESULTS

Introduction

During 2016 Neon Mining has undertaken an extensive program of ridge traverses and talus slope sampling followed by more systematic channel sampling in the most prospecting areas, and drilling.

Exploration Results

The initial results were very encouraging. It was identified as a large anomaly extending over several kilometers in strike length and over 2 km in width (see figure below). Moreover, a malachite anomaly (green dotted line) and bornite zone (solid green line) were also individually identified.

The Results of Geochemical Sampling

One of the most noticeable features of the results is the large spatial spread of high-grade samples, with the single highest value (M16-20) having approximately 15% of Cu, 65 g/t of Au, and 89 g/t of Ag. The high Cu-Au-Ag relationship appears prevalent over the whole site, although the highest gold grades are related to the breccia zones and not the stockwork.

The main aim of this work was to better sample the available outcrop of the Stockwork Zone in the northwest of the area, as well as the collection of other outlying samples.

Two significant intersections were investigated over the Stockwork Zone; the first, perpendicular to strike produced 37 m @ 0.37% Cu, whilst the second along the zone gave 7 m @ 1.4% Cu.

The Mazar-Ashu South Copper Assay Results

In addition to the copper, further gold sampling was undertaken which generally showed that the gold was more prevalent in the east of the area, but also with interesting anomalies discovered to the north and west (1 km west of the stockwork).

Geochemistry

A geochemical model of the combined (Mazar-Ashu North and South) area using such software as Leapfrog, MapInfo (together with Encom Discover, VerticalMap, Surface), and RockWorks was created.

Initially, a cross-correlation matrix was generated.

Cross-correlation matrix

The cross-correlation matrix was the basis of defining the major groups of chemical elements and minerals of mineralization and rock-forming rocks:

  • Mineralization (copper-porphyry type) group: Au-Ag-Cu-Bi-Te-Pb-Se-(Mo)-(W)-(Fe) and (Au + sulfides + sulfosalts + scheelite):
  • Rock-forming group:
    • K-Ba-Cr-Fe-Mg-Y-Be-La-P-Sn-Zr and (K-feldspar + muscovite + sericite + zircon + apatite);
    • Ca-Fe-Mg-Mn-Na-Sr-P-Sc-Ti-V-Zn-Co and (feldspar + hornblende + chlorite + carbonates + rutile).

The further geochemical delineation of the zones of porphyry mineralization was done by cascade overlapping of anomalies of the separate element from the mineralization group. The figure below illustrates the overlapping three of them gold, silver, and copper.

 

Interpretation of geochemical and drilling data

The map of Mazar-Ashu North and South resulted as a composition of element’s anomalies is below:

Geochemical Anomalies

The map with the combined geochemical aureole of porphyry system is below:

The combined aureole of the porphyry system (Au-Ag-Cu-Bi-Mo-Pb)

Mineralogical Studies of Samples from the Mazar-Ashu South Area

Samples collected from the Mazar-Ashu South area were subjected to petrological investigation to better understand the mineralization types. From this work, two major types of mineralization have been identified:

  • Au-galena-covellite-chalcocite-bornite; and
  • Pyrite-molybdenite-chalcopyrite.

Au-galena-covellite-chalcocite-bornite type consists mainly of bornite with the development of secondary copper sulfide minerals like chalcocite and rarely, covellite. Chalcopyrite in this type is observed rarely, in solid solution with bornite. Bornite is presented by fine disseminations and clustered aggregates between amphibole and feldspars within altered rocks.

Photomicrographs of Au-Galena-Covellite-Chalcocite-Bornite Type

Bornite replaces fibers of primary magnetite within host rocks and metasomatic magnetite in skarn. Attachments of bornite to galena and sulfosalts of Pb-Bi-Cu are rarely observed. Micron separations of native gold and silver have been detected within mineralized specimens.

This type of mineralization is observed within stockworks of feldspar veins and injections confined to a monzonite intrusion as well as within bodies of altered gabbroids and metavolcanics.

The pyrite-molybdenite-chalcopyrite type is closely associated with the bornite type. It is more recent and develops at the periphery of the stockwork within zones of rock deformation. It is formed predominantly by chalcopyrite with small amounts of pyrite and molybdenite, sometimes against of backdrop of the development of copper minerals on clustered aggregates of magnetite. Native gold is also observed as micron spots.

Photomicrographs of Pyrite-Molybdenite-Chalcopyrite Type

Channel Sampling

There were three channel sample lines taken at Malakhitovaya Zone. All of them returned encouraging mineralized intersections.

Sample Plan of Malakhitovaya Zone

Channel Sampling of Malakhitovaya Zone

Lines ##1 and 2. Assay Results

Lines ##1 and 2.  Assay Results

The extension of the Malakhitovayae Zone was discovered to south-south-west from channel sample’s lines (see photo below).

Photo of Extension of Malakhitovaya Zone to SSW

Overall the parameters of intersected intervals are following:

  • Line 1. 30 m @ 0.4% Cu and 2.6 g/t Ag, including 7 m @ 0.15 Au.
  • Line 2. 63 m @ 0.6% Cu and 4.5 g/t Ag, including 23 m @ 1.14% Cu, 9.8 g/t Ag and 0.12 g/t Au.
  • Line 3. 72 m @ 0.71% Cu and 4.9 g/t Ag, including 25 m @ 1.14% Cu, 7.2 g/t Ag and 0.13 g/t Au.

Drilling

During the 2017-2019 Drilling Campaign, Neon Mining drilled 3,191.2 meters to-the date. Most of the drilling was concentrated on the south and east flanks of the system due to bad terrain and difficult access to the promising areas. Only in summer 2018, it becomes possible to reach Malakhitovaya Zone where DDH ## 7, 8, 9, and 10 were pushed. DDH ## 7, 8 were completed, and DDH 9 and 10 did not meet the depth it had been planned. DDH # 9 reached the depth of 234 meters (the plan was 330 m). DDH #10 reached a depth of 200 meters (the plan was 350 m).

  • DDH #1 (vertical) or C-1-17
    • Final depth – 204 m;
    • Purpose of drilling – check geophysical (IP dipole-dipole anomaly);
    • Results – intersected zone along whole DDH of weak-strong quartz-sericite-K-feldspar alteration with the highest grade 1.37 g/t of Au.
  • DDH #2 (inclined -650, azimuth – 2800) or C-2-17.
    • Final depth – 300.3 m;
    • Purpose of drilling – check geophysical (IP dipole-dipole anomaly, high resistivity – silica cap (?), epithermal (?));
    • Results – at the depth 230-270 m intersected a zone of medium-strong quartz-sericite-K-feldspar alteration with weak-medium sulfidization (pyrite, chalcopyrite, rare bornite). Copper and gold grades in this interval are elevated.
  • DDH #3 (inclined -80; azimuth – 2800) or C-3-17.
    • Final depth – 320 m;
    • Purpose of drilling – check geophysical (IP dipole-dipole anomaly);
    • Results – at the depth 280-320 m, the zone of medium-strong quartz-sericite-K-feldspar alteration with weak sulfide mineralization (pyrite, chalcopyrite, angelaite) was intersected. The whole interval had an elevated Ag grade (over 1 g/t)
  • DDH #4 (inclined -100; azimuth – 2900) or C-4-17
    • Final depth – 251.5 m (was stopped due to technical issues, strong water inflow);
    • Purpose of drilling – check of geophysical (IP dipole-dipole anomaly) and geochemical anomaly discovered in 2017;
    • Results – at the end of the hole, it was a weak-medium propylite (Q-sericite-chlorite-epidote) alteration.
  • DDH #5 (inclined -100; azimuth – 2800) or C-5-17
    • Final depth – 148.8 m (was stopped due to technical issues, strong water inflow);
    • Purpose of drilling – check of geophysical (IP dipole-dipole anomaly) and geochemical anomaly discovered in 2017;
    • Results – in the interval 2.0-95.0 m, it was a weak-medium rarely strong propylite (Q-sericite-chlorite-epidote) alteration.
  • DDH #5bis (inclined +120; azimuth – 2800) or C-5-17bis. Drilled from the same point as DDH #5.
    • Final depth – 300.3 m (was stopped due to technical issues, strong water inflow)
    • Purpose of drilling – check of geophysical (IP dipole-dipole anomaly) and geochemical anomaly discovered in 2017
    • Results – in the interval 2.0-95.0 m, it was a weak-medium rarely strong propylite (Q-sericite-chlorite-epidote) alteration.
  • DDH #6 (inclined -450, azimuth – 2800) or C-6-18.
    • Final depth – 267.2 m;
    • Purpose of drilling – check geophysical (IP dipole-dipole anomaly, high resistivity – silica cap (?), epithermal (?));
    • Results – at the depth 230-240 m intersected the zone of stockwork-like epithermal quartz and reach the zone of medium-strong quartz-sericite-K-feldspar alteration with weak-medium sulfidization (pyrite, chalcopyrite, rare bornite). Copper and gold grades in this interval are elevated.
  • DDH #7 (inclined +220, azimuth – 350) or C-7-18.
    • Final depth – 300.0 m;
    • Purpose of drilling – reach the Stockwork Zone;
    • Results – at the depth 0-30 m intersected low-medium sulfidization zone with elevated copper and silver; 280-300 m intersected the zone of weak-medium quartz-sericite-K-feldspar alteration with weak-medium sulfidization (pyrite, chalcopyrite, angelaite*, rare bornite). Cu, Ag grades in this interval are elevated.
  • DDH #8 (inclined +250; azimuth – 3200) or C-8-18. Drilled from the same point as DDH#7.
    • Final depth – 311.7 m;
    • Purpose of drilling – reach the Stockwork Zone;
    • Results – at the depth 0-24; 54-56; 84-91; 108-120; 127-138; 156-184; 207-209; 219-224; 286-290; 292-304 m intersected low-medium veinlet-disseminated sulfidization zone with elevated copper and silver. The type of alteration is weak-medium quartz-sericite-K-feldspar alteration (pyrite, chalcopyrite, angelaite*, rare bornite). Cu, Ag grades in this interval are elevated.
  • DDH #9 (inclined +250; azimuth – 350) or C-9-18.
    • Final depth – 234 m;
    • Purpose of drilling – reach the Stockwork Zone;
    • Results –
  • DDH #10 (inclined +250; azimuth – 290) or C-10-18.
    • Final depth – 200 m;
    • Purpose of drilling – reach the Malachite Zone;
    • Results –pending.

Location of diamond drill holes around Stockwork and Malakhitovaya Zones

Evidently, the drill holes are located around the major target – the Stockwork Zone, because of difficult access to both zones. The end of the access road is currently close to the drill site C-3-17 and the road needs to be continued for some about 2 km, which will be done during the next field season.

Although drill holes could not get mineralization yet, they have confirmed it is somewhere around there, by types of alteration and sulfide mineralization. We plan to finalize this by drilling the hole from the top of the system in the 2021 season. 

DEPOSIT TYPE

The Mazar-Ashu South area appears to host a copper-gold porphyry center within a regional scale setting of arc terrane tectonism and magmatism.

The regional setting is important in that the majority of the world’s porphyry systems are related to these tectonic influences as can be seen from their global localization with respect to plate boundaries.

Many porphyry copper-gold (+Mo) systems share similar properties with regard to their host rocks, intrusion types, styles of mineralization, grade distributions, and alteration assemblages.

At Mazar-Ashu, the Project area which covers at least 5km x 1km shows copper and gold mineralization hosted by diorite porphyry stocks and adjacent hornfels-altered sandstone and siltstone rock sequences; this typifies the description of the porphyry copper-gold deposit type given by Sillitoe (2010). Below is shown a schematic porphyry system cross-section.

Less is known at this time about the alteration assemblages, although magnetite does appear to be associated with the main stage of copper-gold mineralization. In addition, from field observations, due to the fact that sulfide copper mineralization is seen at the surface, this might indicate that the oxide zone might be fairly shallow, and with the generally low overall pyrite content, this might preclude the development of large supergene enrichment blankets.

In terms of the erosion level of the deposit, there is insufficient data at this time to determine where Mazar-Ashu sits within the schematic porphyry model as presented by Sillitoe as if a deeper erosion level is chosen (say 3 km), the surface expression of mineralization and alteration will be very different to that seen in the perfect model. At Mazar-Ashu, the presence of a possible silica gold-rich cap might be indicative of a relatively high level of erosion, although more work is required to better understand this.