Challcollo Silver-Gold Mineral Resource Estimate

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# Challcollo Silver-Gold Mineral Resource Estimate

Source: https://aftermathsilver.com/site/assets/files/5659/techreport_challacollo_resource_estimate.pdf
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# Challcollo Silver-Gold Mineral Resource Estimate
AMC Mining Consultants (Canada) Ltd.
BC0767129
200 Granville Street, Suite 202
Vancouver BC V6C 1S4
Canada
T +1 604 669 0044
E vancouver@amcconsultants.com
W amcconsultants.com
Technical Report
Challacollo Silver-Gold Mineral Resource Estimate
Aftermath Silver Ltd.
Region of Tarapacá (Region 1), northern Chile
In accordance with the requirements of National Instrument 43-101 “Standards of Disclosure for
Mineral Projects” of the Canadian Securities Administrators
Qualified Persons:
J.M. Shannon, P.Geo. (ON & BC)
D. Nussipakynova, P.Geo. (ON & BC)
S. Alvarado, Chilean Mining Commission (#0004)
B. Mulvihill, MAusIMM (CP Met), RPEQ
AMC Project 720035
Effective date 15 December 2020
Unearth a smarter way
Challacollo Silver-Gold Mineral Resource Estimate
Aftermath Silver Ltd. 720035
1 Summary
1.1 Introduction
This Technical Report (Report) on the Challacollo Property (Property) has been prepared by AMC
Mining Consultants (Canada) Ltd. (AMC) of Vancouver, Canada on behalf of Aftermath Silver Ltd.
(Aftermath), of Vancouver, Canada. This report is an initial report for the issuer who has entered
into a share purchase agreement with Mandalay Resource Corporation (Mandalay) in which
Aftermath can acquire 100% of the Challacollo Property by making certain staged payments, and
the granting of a 2% Net Smelter Return (NSR) to Mandalay. There are many earlier Technical
Reports on the Property, the most recent of which is titled “NI 43-101 Technical Report for the
Challacollo Silver Project, Region 1, Chile” for Minera Mandalay Challacollo Limitada authored by
Mining Plus and with an effective date of 31 December 2014 (2015 MP Technical Report).
This Report has been prepared by AMC in accordance with the requirements of National Instrument
43-101 (NI 43-101) “Standards of Disclosure for Mineral Projects” and the Canadian Securities
Administrators (CSA) for lodgement on CSA’s System for Electronic Document Analysis and Retrieval
(SEDAR). Aftermath is a Canadian junior exploration company focused on silver and is listed as
AAG.V on Tier 2 of the TSX.V exchange, and as AAGFF on the OTCQB.
1.2 Property description and location
The Property is situated in the province of El Tamarugal, Region of Tarapacá (Region 1), in northern
Chile, about 130 km south-east of the major Pacific port city of Iquique. The approximate
coordinates for the centre of the Property are 20° 57’10” S latitude, 69° 21’20” W longitude, at an
altitude of between 1,300 m and 1,550 m above sea level. Iquique is the capital of the Tarapacá
Region and is the largest regional centre in the area, with a population of 191,000 according to the
2017 census. The city of Pozo Almonte where basic services are also available which is the capital
of the Tamarugal Province is 90 km to the north-north west and has a population of over 15,000.
The Property can be accessed from Iquique initially on Route 16, then travelling south on the Pan
American Highway (Route 5), to the intersection with the Quebrada Blanca and Collahuasi copper
mines access road. This is a private surfaced road and use of this route for access to the Challacollo
Property is through an access agreement. Continuing south east after 30 km a turnoff onto an
unformed gravel road leads to the Property.
The Property comprises Exploitation Concessions created under the Chilean Mining Code of 1932
(Codigo 32) and the Chilean Mining Code of 1983 (Codigo 83). There are 98 Exploitation Concessions
covering 19,362 ha. The concessions do not have a defined expiry date and are valid as long as
payments are made.
Until such time as Aftermath has completed its payments, Mandalay, through its wholly owned
Chilean subsidiary, Minera Mandalay Challacollo Limitada (MMC) own the concessions and they
remain registered in the name of MMC.
MMC has two water rights for use on the project; these are located approximately 18 km east of
the Property. These rights were purchased outright in 2005 by Silver Standard Resources Inc. (Silver
Standard) and registered in the name of MMC in February 2014. The wells are located on private
property.
All surface rights on the Property are owned by the Chilean State.
Challacollo is located in the Atacama Desert, a virtually rainless plateau located between the Pacific
coast and the Andean Mountains. Temperatures are relatively consistent thought out the year, with
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Challacollo Silver-Gold Mineral Resource Estimate
Aftermath Silver Ltd. 720035
an average of 13°C during the winter months of June to August, with a daily minimum of around
8°C. In the summer months of January and February the maximum average temperatures are 20°C,
with a maximum daily recorded temperature of 25.7°C. Daily maximum temperatures experienced
in the summer months are around 25°C. There is zero precipitation in the area of the Property.
Vegetation is absent or sparse and desert based. Most vegetation occurs in water accumulating
basins or depends on getting water out of coastal fog and includes some cacti (Eulychnia),
perennials (Nolana), and mesquites (Prosopis). Animals and insects are generally small, often
coming out nocturnally from below the surface to feed.
The regional infrastructure currently supports significant mining operations at the Quebrada Blanca,
Collahuasi and Cerro Colorado copper mines to the east of Challacollo, as well as SQM nitrate
operations located to the west of Challacollo along Route 5. There is adequate skilled and unskilled
labour available in northern Chile.
High voltage power lines are located along Route 5 and, from the Laguna Substation high voltage
power lines branch to the east to the power the Quebrada Blanca and Collahuasi copper mines. As
part of the Quebrada Blanca expansion project a high voltage power line is currently being
constructed approximately 5 km north of the Property.
There is no exploration camp or other infrastructure at the Property, only core logging and storage
area. The town of Pica was used during past programs as a base of exploration activities. The
Property caretaker resides in Pica. Labour during past exploration programs was sourced in Pica.
Water used for the Mandalay drilling programs was trucked from a well in the community of Las
Pintados.
The Property is sufficiently large enough, at 19,862 ha, to locate a processing plant, tails
management facility and other infrastructure required to operate a mine.
1.3 History
Mining has occurred intermittently at Challacollo since 1772; principally from 1896 through 1931
on an industrial scale under the ownership of Gildemeister. From 1932 to 1980, production
continued at a reduced scale by artisanal miners with no legal title, until the concession owners
reasserted formal control.
In 1980 Gildemeister recovered its rightful possession and exploited the existing ore dumps until
the beginning of 1981. Production records indicate the ore extracted to that date amounted to
approximately 550 t/month, with average grades of 660 g/t Ag and 1.43 g/t Au, with ore being sold
to the Pozo Almonte Agency of Empresa Nacional de Minería (ENAMI). During the second half of
1981, mining was suspended due to a drop in the silver market price.
In 1988 Gildemeister decided to install its own beneficiation plant with 100 tpd capacity, to produce
via leaching and zinc precipitation a silver "cement" for export to Europe, or by flotation a
concentrate for sale to ENAMI's Hernán Videla Lira smelter at Copiapo. At the end of 1989, a
self-sustaining operation was achieved, however with a new drop in precious metals prices the
operation became unprofitable by early 1990. Between 1991 and 1992 approximately 70,000 tonnes
were processed, the plant was removed by the end of 1992.
Modern exploration has occurred in several programs starting in 1995 when initially the Property
was optioned by Empresa Minera Mantos Blancos (Mantos Blancos). Between 1995 and 1996 Mantos
Blancos conducted geological, geophysical surveys and drilling and in December 1996, Mantos
Blancos terminated its option.
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In 1998 Minera Challacollo sold the entire property to Minera Septentrion (Septentrion). Shortly
after purchasing the property Minera Septentrion divided the property into two claim groups and
started to market the property based on two distinct mineral potentials in each block of claims. One
block covered the Challacollo Range, including the Challacollo Silver-Gold Project, while the other
covered a very much larger claim group lying to the southeast that had potential to host porphyry
copper mineralization. This second block of claims is not part of the report and no data referred to
here has been collected on those claims.
Silver Standard optioned the Property from Septentrion in November 2001, completing the
acquisition in 2003 to own 100%. Transfer of titles was completed in February 2014. During the
several programs conducted in 2002, 2003, and 2007 Silver Standard completed surface and
underground sampling, underground surveying, drilling, metallurgical test work, water exploration,
and resource estimates.
Mandalay through MMC purchased the Challacollo Project from Silver Standard and registered their
100% ownership of the Property on 6 February 2014 and 7 February 2014. For clarity, the work
carried out will be referred to as having been carried out by Mandalay. Mandalay undertook surface
sampling and trenching, drilling, metallurgical studies, water exploration, surveying and produced
an unpublished feasibility study on a 660 tpa underground operation.
In November 2019 Aftermath entered into a share purchase agreement with Mandalay but until the
payments to Mandalay are complete the concessions remain registered in the name of MMC.
1.4 Geology and mineralization
The Andes formed in a continental-oceanic plate convergent setting with subduction of the Nazca
Plate under the South American Plate. This resulted in three distinctly north-south oriented domains
which are the result of differential shortening recording periods of Andean deformation and uplift.
The large-scale physiography of the fore-arc region is considered as a direct expression of the
tectonic processes operating during the late Cenozoic. The Challacollo deposit is located in the
Central Depression which is located immediately east of the Coastal Cordillera.
The Challacollo Range which hosts the Property is interpreted as being a fault-bound prism brought
to the higher elevations by the inferred Challacollo Reverse Fault, and its associated back thrust
fault. Both the Challacollo Fault and the back-thrust fault are covered by Neogene and Paleogene
sediments that fill the Central Depression.
The volcanic and sedimentary units exposed in the Challacollo Range strike approximately 030° and
dip about 25° to the southeast. Hence the oldest outcropping units are on the Challacollo Ridge and
the youngest being on the south eastern slopes. The beds steepen locally near faults such as the
Lolón Structure where dips increase to as much as 50°. These vein-fault structures generally occur
parallel to the north-south trending normal faults which bracket the Challacollo Range.
The local geology consists of the Upper Jurassic Challacollo Formation, which is unconformably
overlain by the Upper Cretaceous Challacollo Volcanic Complex (CVC). The Challacollo Formation is
a sequence of shales with subordinate interbedded limestone, siltstone, calcareous, siliceous
siltstone, sandstone, and fine quartzite, with interlayers of gypsum near the top of the sequence.
The CVC which has been dated at between 83 to 80 Ma consists o

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