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  • Significant high-grade VMS deposit with robust resource expansion opportunities
  • Located in the prolific Iberian Pyrite Belt which hosts numerous world class mines
  • Established mining district with solid infrastructure supporting accelerated development

Deposit Type: Volcanogenic Massive Sulphide (VMS) 

Metals: Zinc, Lead, Silver, Copper, Gold, Tin

Location: Grândola, Setúbal District, Portugal

Ownership: 25%*, option to earn up to 80%

Status: Exploration Stage

Infrastructure: Access to roads, power and water

North Zone M&I Mineral Resource*

Massive Sulphide & Gossan

10.33 Mt at 9.06% ZnEq

South Zone M&I Mineral Resource*

Stockwork

2.47 Mt at 1.54% CuEq

Central & South Zone Inferred Mineral Resource*

Stockwork

7.79 Mt at 1.43% CuEq

Overview

In June 2018, Ascendant entered into an agreement with TH Crestgate GmbH to acquire an initial 25% interest in its Portuguese subsidiary Redcorp - Empreendimentos Mineiros, Lda (Redcorp), which holds an 85% interest in the polymetallic Lagoa Salgada volcanogenic massive sulphide (VMS) Project, as well as an option to earn up to an 80% interest in Redcorp upon completion of certain milestones.

The Lagoa Salgada Project is located within the north-western section of the prolific Iberian Pyrite Belt in Portugal, approximately 80 km southeast of Lisbon and is accessible by national highways and roads. The Project is comprised of a single exploration permit covering an area of approximately 10,700 hectares. The Project represents an early-stage, potentially high-grade, polymetallic zinc-lead-copper exploration opportunity in a low risk, established and prolific jurisdiction.

The Iberian Pyrite Belt (IBP) is host to some of the world’s largest VMS deposits (80) and mines such as Neves-Corvo (Lundin Mining Corporation), Aguas Tenidas (Trafigura Mining Group) and Aljustrel (ALMINA). It represents the largest concentration of massive sulphide deposits in the world, forming an arch through Portugal and Spain about 250 km long and 30-50 km wide and has produced more than 1,750 million tonnes of massive sulfide ore and 2,500 million tonnes of mineralized stockwork over the past hundred years.

The Project represents a low-cost entry opportunity to gain exposure to a known, high-grade VMS deposit that has significant exploration potential to expand the resource in the near term. The region has a long history of large-scale mineral discovery with the majority of the deposits and mines demonstrating multiple zones typical of VMS style deposits. The Regional Residual Bouguer Gravity Map has identified numerous gravity anomalies on the Lagoa Salgada property. Two of these are coincidental with the known deposits, the North Zone (main massive sulphide zone) and the Central and South Zones (stockwork zones).

* Notes: Ascendant owns a 25% interest in Redcorp – Empreendimentoes Mineirs, LDA., which owns an 85% interest in the Lagoa Salgada Project as well as acts as the operating entity. Ascendant has an option to increase ownership to 80% upon completion of certain milestones and payments. On a pro rata basis Ascendant currently owns an effective 21.25% of the Project. Resources are shown on a 100% basis. 

History

In 1992, the Lagoa Salgada deposit was discovered by a team from the Portuguese Geological Survey, known then as the Serviço de Fomento Mineiro (SFM). The deposit is completely covered by a thick sequence of Tertiary sedimentary rock, averaging 135 metres thick. The discovery was made through diamond drill testing of a geophysical gravity anomaly.

In 1994, the area was awarded to a mining consortium comprised of Rio Tinto Zinc (RTZ) and Empresa Desenvolvimento Mineiro SA (EDM), a Portuguese government agency, who held the property from 1994 to 2000. Between 1994 and 1999, the consortium completed an airborne magnetic survey of the property and drilled 20 widely spaced diamond drill holes. In addition to the magnetic survey, RTZ performed limited downhole geophysics, electro-magnetic surveys, and limited soil sampling.

In October 2004, the Property was acquired by Redcorp which at the time was called Redcorp Ventures Ltd. In 2005, Redcorp drilled six holes totaling 2,286 metres. Drilling continued in 2006, 2007 and 2008 with an additional 16 holes totaling 8,692 metres being completed.

In 2009, Portex acquired a 100% interest in Redcorp to develop the LS-1 deposit on the property. From 2009 to 2012 Portex’s exploration activities included a diamond drilling and downhole geophysical surveys.

In 2015, TH Crestgate GmbH acquired a 100% stake in Redcorp which holds an 85% interest in the and operator status of the Project. EDM holds the remaining 15% interest in the Project. The majority of Redcorp’s exploration activities were focused on its 2016-2017 diamond drill program, which formed the basis for the Mineral Resource Estimate and Technical Report completed in January 2018 that defined resources at both the LS-1 and LS-1 Central deposits.

PEA

The Preliminary Economic Assessment (“PEA”) for the Lagoa Salgada project demonstrates the potential viability of mining the Measured, Indicated and Inferred Mineral Resources of the North Zone only. The study is based upon the Company’s current Mineral Resource Estimate for the North Zone reported in the recently released National Instrument 43-101 Technical Report with an effective date of September 5, 2019.

The PEA outlines a robust and compelling economic assessment for Lagoa Salgada as it assumes a two-stage underground mining development scenario, with single trackless ramp access, transverse sub-level open stoping method with pastefill. Ventilation and secondary escape ways are planned through raise-bored holes to surface. Milling rates of 2,700 tonnes per day in a standard process circuit is anticipated, with primary crushing, grinding, flotation and leaching of tailings to produce concentrates including lead, zinc, copper and tin, as well as gold and silver doré. There is ample opportunity for extensive expansion from future exploration work to define additional resources to extend the mine life or increase the scale of the outlined operation.

Highlights of the key project metrics are provided in the following table on a 100% basis:

PEA Key Highlights

Notes to Table:

1 The project economics have been calculated using consensus prices at the time of the Resource Estimate report in September 2019

The PEA was prepared by AMC Mining Consultants (Canada) Ltd (AMC) with contributions from Resource Development Inc (RDI) for Mineral Processing and Micon International Limited (Micon), who estimated the Mineral Resources.

The PEA is preliminary in nature, as it includes Inferred Mineral Resources that are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as Mineral Reserves, and there is no certainty that the preliminary economic assessment will be realized.

Mining

The mine design is based on a single decline access from surface at a 12.6% gradient. Decline access is via a 30-meter deep boxcut. Stopes are accessed from level access drives in the north and the south of the deposit. Interlevel spacing varies between 24 meters and 35 meters. All mineralized material and waste development is mined with a 4.5 meter by 4.5 meter end profile. Ore and waste will be hauled to surface using 30 tonne trucks.

The deposit is planned to be mined using transverse sub-level open stoping with pastefill at a production rate of approximately 1 Mtpa. Crosscuts will access the deposit with drives developed laterally across the mineralization. Drives in mineralization will be placed 12.5 meters apart along strike, with stopes approximately 25 meters to 35 meters high, 12.5 meters wide and 25 meters in length. Stope heights in the Gossan tend to be generally less, approximately 20 meters high. A slot will be cut at the end of the mineralization and consecutive rings blasted in a retreating fashion over the full stope length back to the crosscut. Uphole drill rings from the existing drives in the Massive Sulphide will be drilled to extract the mineralization from the overlying Gossan deposit. Ventilation and escape raises will be raise-bored from surface.

The mine life of 9 years is based on a 2,700 tonne per day mining rate. Mine life is based on average head grades of 2.44% Zn, 2.85% Pb, 0.34% Cu, 0.16% Sn, 0.75 g/t Au, 69.8 g/t Ag. Unplanned dilution due to the extraction of the stope was assumed to be 8% for the Gossan zone and 5% for the Massive Sulphide zone. Mining recovery of 90% was assumed for the Gossan and 93% for the Massive Sulphide.

Wireframe of the North Zone Mineral Resource Deposit Conceptualized Mining Scenario of the North Zone Metal Production by Year

Metallurgy and Processing

The company has completed initial scoping level metallurgical study with Empresa de Perfuração e Desenvolvimento Mineiro, S.A. (EPDM), Portugal, Grinding Solutions Ltd (GSL), UK, and Wardell Armstrong (WAI), UK in 2019. These non-optimized results indicated that conventional polymetallic process flowsheet is capable of recovering copper, lead, zinc, gold and silver. The flotation tailings will be leached for additional gold and silver values. The oxide ore can be leached to recover precious metals. The leach residue can be sulphidized to recover oxide lead. The final tailing has sufficient tin values and can be recovered by flotation.

The projected recoveries and concentrate grades in the table below are estimated for the project based on extensive experience working with polymetallic ores. Additional testing is planned to confirm the concentrate recoveries and grades.

Metallurgy and Processing Table

Off-site charges include transport of concentrates either to a European smelter or to the port of Lisbon. Additional charges have been considered for lead and tin overseas. Life-of-mine concentrate treatment (including penalties) and transport charges were assumed to be $240/dmt for lead, $270/dmt for zinc and $530/dmt for tin, with standard offtake and refining terms for all metals.

Infrastructure

Lagoa Salgada is situated in southern Portugal about 100km south west of Lisbon, in close proximity to the town of Grândola, and is currently accessed via paved roads to Cilha do Pascoal, followed by 4 km of gravel roads to the mine site. Some improvement to the gravel road to the mine site may be required to accommodate heavy construction traffic.

The site will require an office, changeroom, shop and warehouse as well as storage for fuel, laydown areas, site fencing, and security building. An allowance for a total of 2,600 m2 of building space has been included in the PEA.

Total power requirement for the mine and mill is estimated to be 15 MW. There is ample opportunity to connect to the national grid with both 400 kV and 30 kV transmission lines operating within 7 km of the project site. However, for this study, a conservative allowance has been made to run a 30 kV, 20 MVA transmission line from the existing sub-station at Grândola.

Tailings and waste rock will be disposed of through the use of a dry-stack facility. Total tailings for life of mine are estimated at 7.5 Mt with a further 0.7 Mt of waste rock. Approximately 55% of tailings will be disposed of in the mined-out stopes via the pastefill system. The remaining 4.1 Mt of tailings and waste must be accommodated in the dry stack facility. The base of the facility will be lined, and a low perimeter berm and ditch will capture any precipitation run off during the life of mine. Run off will be collected in a settling pond for use by the mine as service water.

Regional precipitation averages 700 mm per year, and it is anticipated that the site will have a net neutral water balance once the initial dewatering of the mine is complete. All water from the mill will be reused.

Total annual water gain through precipitation and mine dewatering is estimated to be approximately 325,000 m3. Loss to the tailings is estimated at 250,000 m3 per year with evaporation accounting for the remaining loss. A complete climate and water balance study is required.

It is anticipated that any make-up water that may be required will be obtained via local wells on site. Should this not be adequate, water can be obtained from the Sado River approximately 5 km from the project site.

A settling pond with capacity of 100,000 m3 will be established to hold precipitation run-off during the rainy season as well as mine and mill water discharge.

AMC has assumed ground water inflow of 5 L/s. Water will be discharged via a staged pump system with pumps located on 3 levels staging to surface.

Operating Costs

The LOM unit operating costs are estimated to be $49.43/t milled. Costs are based on benchmark data from other local operations and local labour costs. Mining is estimated to be $16.84/t milled, Processing $29.17/t milled and General and Administration $3.42/t milled.

Average LOM Unit Costs:

Capital Costs

The total capital cost estimate is $183 million, or $25.23/t milled. Initial Capex of $162.7 million with a four-year payback period and $20.2 million ($3.03/t milled) in sustaining capital.

Total Capital Expenditure Breakdown:

Capital CostsTable

Project Economics

The project shows robust economic results with a pre-tax NPV at 8% of $137 million and an IRR of 37%, and an after tax NPV at 8% of $106 million and IRR of 31%.

Project economics are based on a 9-year mine life with a 4-year payback period, with positive after-tax cash flow commencing in Year 3.

Annual After-Tax Cash Flow

Sensitivities

Project economics are most leveraged to the zinc price yet also highly leveraged to the lead price. A 15% increase to the zinc price results in a post-tax NPV8% increase of 23% to $130 million. Similarly, a 15% increase to the lead price results in a post-tax NPV8% increase of 20% to $127.7 million.

The project economics have been calculated using consensus prices at the time of the Resource Estimate report in September 2019.  Based on January 13, 2020 spot prices of $1.08/lb Zn, $0.86/lb Pb, $2.78/lb Cu, $18/oz Ag, $1,560/oz Au and $7.68/ln Sn, the project economics remain robust with an After-tax IRR of 24% and NPV8% of $73M (C$96M @$1.31CAD/USD).

Economic Sensitivity Analysis - After-Tax NPV @ 8.0%

Environmental & Permitting

In terms of Environmental Licensing, an Environmental Scoping Proposal (PDA) has already been prepared and submitted to the Environmental authorities for the start of the Environmental Impact Assessment (EIA), in accordance with Portuguese regulations, which has already been approved by the Environmental Impact Assessment Authority (APA).

Within 45 days of Ascendant’s press release dated January 14, 2020, reporting the results of the PEA, the Company will file with regulatory authorities a Technical Report prepared in accordance with NI 43-101 that documents the PEA study and supports the current disclosure.


Geology and Mineralization

The Lagoa Salgada property is located at the north-western end of the Iberian Pyrite Belt ("IPB"); a 250 km long by 30-50 km wide, geographical and geological area that extends along much of the southern Iberian Peninsula, from Spain into Portugal. The belt is a thrust faulted volcano sedimentary sequence with local sub-aqueous volcanic centers that host volcanogenic massive sulphide (VMS) deposits. VMS deposits are stratabound and partly strataform, deposits of sulphide minerals formed by hydrothermal fluids that are exhaled onto the seafloor and can be classified into three types according to their mineral content: Cu-type, Zn-Cu-type and Zn-Pb-Cu-type. VMS deposits are generally Cu-rich at the base and Zn-rich at the top. The deposits are generally interpreted to be syngenetic in origin, however, mineralization ranges from sulphide precipitates to re-worked sulphide/silicate sediments and local sulphide replacement and remobilized mineralization located in close proximity to felsic submarine volcanic centers. Within the Iberian Pyrite Belt, VMS deposits vary in size from a few hundred thousand tonnes to greater than 200 million tonnes and have been dated at Upper Devonian to Lower Carboniferous in age. The Iberian Pyrite Belt is one of the most important VMS districts in the world, hosting more than 80 known deposits, and has been mined for more than 4500 years.

The Lagoa Salgada Deposit is a blind deposit as the entire property is covered by a palaeo-fluvial fan that ranges in thickness up to 200 metres within the Tertiary Sado Basin and averages 135 metres over the deposits. The Tertiary sedimentary rocks lie unconformably on top of the rocks of the Volcano-Sedimentary Complex of the Iberian Pyrite Belt. This sequence of rocks ranges in age from Upper Famenian to Middle Visean and are represented on the Property by a northwest-southeast lineament, approximately 3.5 km long and 1 km wide.

There are four types of mineralization at Lagoa Salgada:

• Primary massive sulphide mineralization.
• Gossan mineralization resulting from weathering of the primary mineralization.
• Copper-rich stringer mineralization.
• Zinc, lead, copper, silver stockwork mineralization which appear to be later and structurally controlled. (epigenetic)

To date, the mineralized system at the North Zone has been drill tested over a strike length of approximately 450 metres and appears to be open to the south and east. Recent ground IP survey has identified an anomaly that extends over 1.7 km to the southeast along strike, and similar to that of the North Zone deposit. The furthest of this anomaly has been drill tested and hosts the Central and South Zone deposits.

Gossan mineralization results from the weathering of primary massive sulphide mineralization. It is preserved at Lagoa Salgada as a result of the Tertiary sedimentary rocks covering the palaeosurface, in a situation analogous to the Las Cruces copper deposit in Spain. Gossan mineralization at Lagoa Salgada seems to be comprised of a lead-rich leached cap, underlain by a precious metal-rich, supergene enrichment zone.

Copper-rich stringer mineralization consists of sulphide veins and stringers in chloritic altered volcanic rocks, and represents alteration associated with the feeder system to the massive sulphide mineralization. This type of mineralization is well-developed in other IPB deposits such as Feitais (Aljustrel) and Neves Corvo.

The zinc, lead, copper and silver-rich stockwork mineralization consist of open space filling of sulphide veinlets in chloritic altered volcanic rocks. This mineralization appears to be later and structurally controlled between the brittle and ductile deformed rocks.

The Lagoa Salgada deposit is a VMS deposit that consists of at least one distinct lens of massive sulphide mineralization that was deposited on the sea floor as a result of precipitation from the venting of metal-rich hydrothermal fluids. These fluids typically exploit faults and fractures planes as fluid pathways and create a large zone of hydrothermal alteration in the rocks below the deposits. VMS deposits are typically characterized by clusters of on echelon lenses occurring within a distinct stratigraphic interval. The extensive alteration zone on the Property suggests that hydrothermal activity was prolonged over a long period of time and that additional lenses associated with separate alteration zones may exist.

The North Zone consists of a massive sulphide lens with a slight anticlinal fold with a current strike length of approximately 450 metres long by 175 metres wide. The North Zone deposit is bound to the west by a sharp fault contact and appears to remain open to the east and to the south. It is also host to stockwork mineralization, bounding the massive sulphides at depth and partially to the east. A gossan cap of supergene mineralization has been outlined that overlies the majority of the deposit.

The Central and South Zone deposits appear to be stockwork mineralization and is generally enriched in zinc, lead, copper and silver, however, pyrite poor as compared to the North Zone. The upper northern portion of the Central & South Zone deposits appear to be Pb-Zn enriched, as noted in one drill hole (LS_ST_01). They are also overlain by the tertiary sedimentary units. Both the copper and the lead-zinc enriched portions of the deposit have not yet been fully delineated.

Exploration work in 2018 and 2019 was designed to expand and better defined both deposits and to investigate the region between the deposits where the IP ground survey has outlined a continuous anomaly. In addition, some regional exploration work on the rest of the property is also planned to prioritize future exploration targets.