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  • Significant high-grade VMS polymetallic 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: Polymetallic 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

M&I Mineral Resource*

7.84 Mt at 8.38% ZnEq

Inferred Resource*

12.82 Mt at 6.37% ZnEq

Measured Resource*

1.76 Mt at 11.02% ZnEq

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 and mines such as Neves-Corvo (Lundin Mining Corporation), Aguas Tenidas (Trafigura Mining Group) and Aljustrel (private). It represents the largest concentration of massive sulphide deposits in the world, forming an arch through Portugal and Spain about 240 km long and 35 km wide and has produced more than 300 million tonnes of massive sulfide ore 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 two known deposits, LS-1 (in the Main Massive Sulphide Zone) and LS-1 Central (in the Stockwork Zone).

* 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. Ascendant holds a 25% interest in Redcorp, the operating subsidiary which holds an 85% interest in the Lagoa Salgada Project.

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.

Geology and Mineralization

The Lagoa Salgada property is located at the north-western end of the Iberian Pyrite Belt; 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 250 known deposits, and has been mined for more than 5000 years.

The entire Lagoa Salgada 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 Lagoa Salgada 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 LS-1 has been drill tested over a strike length of approximately 425 metres and appears to be open to the south and east. Recent ground IP survey has identified an anomaly that extends over 1.6 km to the southeast along strike, and similar to that of the LS-1 deposit. The furthest of this anomaly has been drill tested and hosts the LS-1 Central deposit.

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 LS-1 consists of a massive sulphide lens with a slight anticlinal fold with a current strike length of approximately 425 metres long by 175 metres wide. The LS-1 deposit is bound to the west by a sharp fault contact and appears to remain open to the east and to the south. The LS-1 deposit 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 LS-1 Central deposit appears to be stockwork mineralization and is generally enriched in zinc, lead, copper and silver, however, pyrite poor. as compared to the LS-1 deposit. The upper northern portion of the LS-1 Central deposit appears to be Pb-Zn enriched, as noted in one drill hole (LS_ST_01). The LS-1 Central deposit is 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 into 2019 is 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.

Exploration

In 2018, Ascendant and TH Crestgate GmbH together through Redcorp executed on an exploration program which included 20-holes totaling 6,950 metres and an initial geophysics program. This drill program included 12 holes (3,964 metres) in the Main Massive Sulphide Zone and 8 holes (3,113 metres) in the Stockwork Zone. The program has been very successful at confirming and expanding high-grade mineralization in the Main Massive Sulphide Zone and in expanding and improving the continuity of the sulphide mineralization in the Stockwork Zone. Results from the Main Massive Sulphide Zone indicate additional massive sulphide mineralization at grades in excess of 10% ZnEq.

The identification of cassiterite (SnO2) (tin mineralization) associated with the Main Massive Sulphide Zone has contributed significantly to the higher-grade results. The IBP is known for having areas enriched in tin, however, there had been no previous assaying for tin in the historic drill holes at Lagoa Salgada until this program. Significant tin values were recognized in the 2018 drill holes and in the historic (2017) drill holes in the gossan, massive sulphide and stringer zones of the Main Massive Sulphide Zone. In many of the holes, the results are material and add an average 1.5% to the ZnEq grade.

Concurrent geophysical work confirmed a strong, continuous 1.6 km long chargeability anomaly which includes the Main Massive Sulphide and Stockwork Zones. A Regional Residual Bouguer Gravity anomaly coincides with the Chargeability anomaly. Also the gravity map identifies numerous additional anomalies within Lagoa Salgada’s property boundary.

Lagoa Salgada with Geophysical Maps Showing Coincidental Anomalies 




 

Plan View of the 2018 Planned Drill Holes

 

Drill holes in this program were collared in an area targeting the eastern expansion of the known main volcanogenic massive sulphide mineralization contained within the current Mineral Resource Estimate as defined in the National Instrument 43-101 report dated January 5,2018 and targeting expansion of the Stockwork Zone.

Significant thickness of gossan and massive sulphide mineralization were intersected in holes LS_MS_07, LS_MS_16 through LS_MS_20. In several of the holes, including LS_MS_07, LS_MS_16, LS_MS_18 and LS_MS_19, a second massive sulphide horizon was intersected on the west side of a major fault identifying a possible new lens.

In addition to the drill program, ground and downhole IP surveys have identified a chargeability anomaly 1.6 kilometres long by 200-300 metres wide that is coincidental with the sulphide mineralization both in the Main Massive Sulphide Zone and the Stockwork Zone. This broad N-S zone of elevated chargeability can be traced from the Main Massive Sulphide Zone southwards to beyond the zone where the Stockwork Zone was drilled in 2018 with no evidence of a gap or eastward offset in mineralization suggested by a 2016 IP/Res survey. The IP 3D model suggests that the drilling at the Main Massive Sulphide Zone is coincident with the chargeability anomaly. However, the model for the Stockwork Zone suggests the stronger part of the anomaly lies to the east and remains untested. In addition, Pseudosections prepared for the 2018 IP lines indicate a second target southeast of the Main Massive Sulphide Zone, near the eastern end of lines 8-10 and extending as far south as line 14 that is also untested.

The IP anomaly is also coincident with the more extensive Regional Residual Bouguer gravity anomaly that stretches southeast by approximately 8km to the Rio de Moinhos Target, highlighting a significant number of targets for the future.

2018 Significant Assay Results and Drill Hole Details

 

Mineral Resources

The Mineral Resource Estimate for the Lagoa Salgada Project in Portugal is prepared in accordance with National Instrument 43-101 – Standards for Disclosure for mineral Projects with an effective date of February 8, 2019. 

The Mineral Resource Estimate was announced in the Company's press release dated February 13, 2019. A Technical Report will be filed with SEDAR with in 45 days of the aforementioned press release. 

Total Mineral Resource Estimate - Effective February 8, 2019

 

 

 

 

 

Average Grade

 

 

Category

MinZones

Tonnes (kt)

Zn-Eq2 (%)

Cu (%)

Zn (%)

Pb (%)

Sn (%)

Ag (g/t)

Au (g/t)

Measured

All Zones

1,761

11.02

0.38

3.09

3.19

0.15

62.41

0.84

Indicated

All Zones

6,082

7.61

0.50

2.09

1.84

0.09

48.61

0.40

M + I

All Zones

7,843

8.38

0.47

2.31

2.15

0.10

51.71

0.50

Inferred

All Zones

12,823

6.37

0.36

1.68

1.63

0.04

38.62

0.61

Mineral Resource Estimate  By Zone

 

 

 

 

 

 

Average Grade

 

 

 

Category

MinZones

Tonnes (kt)

Zn-Eq (%)

Cu (%)

Zn (%)

Pb (%)

Sn (%)

Ag (g/t)

Au (g/t)

 

Measured

Total

1,761

11.02

0.38

3.09

3.19

0.15

62.41

0.84

North
Zone

Indicated

Total

4,293

8.71

0.47

2.18

2.22

0.12

58.73

0.54

M + I

Total

6,054

9.38

0.44

2.44

2.50

0.13

59.80

0.63

Inferred

Total

7,847

7.43

0.31

1.90

2.22

0.07

50.34

0.58

South
Zone

Indicated

SW2

1,789

4.99

0.58

1.88

0.95

0.00

24.33

0.07

Inferred

SW2

3,899

4.50

0.52

1.65

0.89

0.00

22.36

0.06

Central
Zone

Inferred

Total

1,078

5.41

0.11

0.17

0.06

0.00

12.15

2.89

Notes: 

Mineralized Zones, GO=Gossan, MS=Massive Sulphide, SW=Stringer, SW2=Stockwork

Cut-off: Zn-Eq ≥ 3.00%

Zn-Eq = [Zn%]+([Cu%]*2.652)+([Pb%]*0.913)+([Au g/t]*1.585)+([Ag g/t]*0.025)+([Sn%]*7.565)

Densities: GO = 3.11, MS = 4.85, SW = 2.91, SW2 = 2.91

The Mineral Resource Estimate contents have been reviewed and approved by Charlie Murahwi, M.Sc., P.Geo., Pr. Sci. Nat., FAusIMM, Senior Geologist, Micon International Limited.

The scientific and technical information  has been reviewed and approved by Robert Campbell, P.Geo., Vice President, Exploration for Ascendant Resources Ltd, whom is a Qualified Persons as defined in National Instrument 43-101.

 

 

Characteristics of VMS Deposits

Volcanogenic (Volcanic) massive sulphide (VMS) deposits, are major sources of zinc, copper, lead, silver and gold. They typically occur as lenses of polymetallic massive sulphide that form on the seafloor in submarine volcanic environments and are classified according to base metal content. They form from metal-enriched brines associated with seafloor hydrothermal convection. Their immediate host rocks can be either volcanic or sedimentary. Because of their polymetallic content, VMS deposits continue to be one of the most desirable deposit types for security against fluctuating prices of different metals. There are close to 850 known deposits worldwide.

The most common feature among all types of VMS deposits is that they are formed in extensional tectonic settings, including both oceanic seafloor spreading and back arc environments. Most, but not all, significant VMS mining districts are defined by deposit clusters formed within rifts or calderas. Their clustering is further attributed to a common heat source that triggers large-scale subseafloor fluid convection systems. These subvolcanic intrusions may also supply metals to the VMS hydrothermal systems through magmatic devolatilization. As a result of large-scale fluid flow, VMS mining districts are commonly characterized by extensive semi-conformable zones of hydrothermal alteration that intensifies into zones of discordant alteration in the immediate footwall and hanging wall of individual deposits. VMS camps can be further characterized by the presence of thin, but areally extensive, units of ferruginous chemical sediment formed from exhalation of fluids and distribution of hydrothermal particulates.

Most VMS deposits have two components (see Figure 1 below). There is typically a mound-shaped to tabular, stratabound body composed principally of massive (>40%) sulphide, quartz and subordinate phyllosilicates, and iron oxide minerals and altered silicate wall-rock. These stratabound bodies are typically underlain by discordant to semi- concordant stockwork veins and disseminated sulphides. The stock-work vein systems, or “pipes”, are enveloped in distinctive alteration halos, which may extend into the hanging-wall strata above the VMS deposit.

Figure 1: Cross section of a VMS deposit



Source: Volcanogenic Massive Sulphide Deposits, Alan G. Galley, Mark D. Hannington, And Ian R. Jonasson, 2007.

Technical Report