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Brazil

Santa Rita Expansion Project

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Overview

Mine TypeUnderground
StagePreliminary Economic Assessment
Commodities
  • Nickel
  • Copper
  • Cobalt
  • Palladium
  • Platinum
  • Gold
Mining Method
  • Sub-level caving
Mine Life... Lock
SnapshotThe CPR presents a PEA on the underground potential at the Santa Rita mine. An infill drill program and prefeasibility study on the underground project are currently underway.
Related AssetSanta Rita Operation

Owners

SourceSource
CompanyInterestOwnership
Appian Capital Advisory LLP 100 % Indirect
Atlantic Nickel Mineração Ltda. (operator) 100 % Direct
The Santa Rita nickel mine is owned and operated by Atlantic Nickel Mineração Ltda. (Atlantic Nickel), a subsidiary owned by Appian Capital Advisory LLP (Appian Capital).

Deposit type

  • Intrusion related
  • Magmatic
  • Laterite

Summary:

Mineralisation within the Fazenda Mirabela intrusion is considered to be an example of a magmatic nickel–copper sulphide deposit.

The Fazenda Mirabela intrusion, which hosts mineralisation at Santa Rita, is located within the Archean–Paleoproterozoic Itabuna–Salvador–Curaça orogenic (ISC) belt. It consists of a lowpotassium calc-alkaline plutonic suite of rocks that includes intercalated metasedimentary rocks, gabbro, and basalt. The Fazenda Mirabela mafic–ultramafic body intruded granulite of the ISC. The lower zone of the intrusion consists of olivine-rich cumulates, primarily dunite to harzburgite, and is capped by pyroxenite; the upper zone consists primarily of gabbroic cumulates, consisting of gabbronorites to norites.

The intrusion is oval-shaped in plan view, with outcrop dimensions of approximately 4.0 km by 2.5 km and original stratigraphic thickness of at least three kilometres. In cross-section, the intrusion extends to a vertical depth of approximately 1,400 m.

Three generations of deformation phases are recognised, including thrust duplexes, quartz–feldspar pegmatite dikes intruded into basement lithologies, and folding. The major alteration type is fracture or structurally controlled serpentinisation.

A significant laterite profile, typically 25 m thick, developed over the dunite–harzburgite lithologies, but is absent or poorly developed over other lithologies.

The Santa Rita deposit is characterised by the lateral continuity of the mineralisation (approximately 2 km along strike and 1.3 km down dip). Nickel and copper sulphides form stratiform bodies that are generally parallel to the lithostratigraphic contacts. The primary lithological host rocks are orthopyroxenite, olivine orthopyroxenite, harzburgite, and dunite.

The mineralisation that supports the Mineral Resource estimate is primarily hosted in disseminated sulphides, 2% to 5% sulphide by volume. Some evidence of vein-like semi-massive sulphides is also noted, but this mineralisation type is not economic. On average, sulphide mineralisation comprises 52% pentlandite, 7% violarite ((Ni,Fe)3S4), 18% chalcopyrite, 14% pyrite, and 9% pyrrhotite as granular intercumulus aggregates. Traces of PGMs also occur, however, these elements appear to be included within the structure of the principal sulphides.

The Fazenda Palestina mafic–ultramafic intrusion is located 25 km to the south-southwest of the Santa Rita Mine. The intrusion cluster measures approximately 5 km east-west by 3 km north-south and, similar to the Fazenda Mirabela intrusion, has intruded granulite facies country rocks. The two dominant lithologies within the intrusion are orthopyroxenites and, to a lesser extent, gabbronorites. The deposit is approximately 1,350 m long, 50 m wide, and extends to a depth of at least 350 m. Pentlandite and chalcopyrite are the dominant nickel and copper minerals, respectively.

Three deformation phases are currently recognised in the Santa Rita open pit area:
• The oldest phase forms thrust duplexes on the scale of tens to hundreds of metres in the open pit. The deformation strain is oriented northeast–southwest and forms west–northwest to east–southeast trending structures that converge to the southwest.
• The second deformation comprises a suite of quartz–feldspar pegmatite dikes developed in basement lithologies.
• Folds with a north–south axis form the third phase of deformation.
A dolerite (diabase) dike was observed in the Santa Rita open pit cross-cutting the Santa Rita intrusion at a 120° azimuth. The dike is approximately 20 m thick and follows previously existing fracture planes that were reactivated during dike intrusion.

There are two styles of sulphide mineralisation:
• Disseminated sulphides, 2% to 5% sulphide by volume, hosting the mineralisation that supports the Mineral Resource estimate;
• Vein-like semi-massive sulphides that have no economic interest.

On average, sulphide mineralisation comprises 52% pentlandite, 7% violarite ((Ni,Fe)3S4), 18% chalcopyrite, 14% pyrite, and 9% pyrrhotite as granular intercumulus aggregates. Minor sulphide phases identified in thin sections include mackinawite ((Fe,Ni)9S8), millerite (NiS), poorly defined lowtemperature iron sulphides, cubanite, bornite and chalcocite, along with traces of native copper. Individual sulphide aggregates are commonly not more than 0.5 mm to 1.0 mm in size; however, larger cumulates up to 30 mm are observed locally. Finer and more widely disseminated sulphide grains include abundant chalcopyrite.

Reserves

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Mining Methods

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Comminution

Crushers and Mills

Milling equipment has not been reported.

Processing

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Production

CommodityProductUnitsAvg. AnnualLOM
Nickel Payable metal kt 567
Nickel Concentrate kt 4,888
Nickel Equivalent Payable metal kt 24673
Copper Payable metal M lbs 304
Cobalt Payable metal M lbs 11
Palladium Payable metal koz 158
Platinum Payable metal koz 214
Gold Payable metal koz 101

Operational metrics

Metrics
Annual processing capacity  ....  Subscribe
Waste tonnes, LOM  ....  Subscribe
Ore tonnes mined, LOM  ....  Subscribe
Tonnes processed, LOM  ....  Subscribe
* According to 2023 study.

Production Costs

CommodityUnitsAverage
All-in sustaining costs (AISC) Nickel USD  ....  Subscribe
C1 cash costs Nickel USD  ....  Subscribe
Assumed price Palladium USD  ....  Subscribe
Assumed price Platinum USD  ....  Subscribe
Assumed price Cobalt USD  ....  Subscribe
Assumed price Nickel USD  ....  Subscribe
Assumed price Copper USD  ....  Subscribe
Assumed price Gold USD  ....  Subscribe
* According to 2023 study / presentation.
** Net of By-Product.

Operating Costs

Currency2023
UG mining costs ($/t milled) USD 12.9 *  
Processing costs ($/t milled) USD  ....  Subscribe
G&A ($/t milled) USD  ....  Subscribe
* According to 2023 study.

Project Costs

MetricsUnitsLOM Total
Initial CapEx $M USD  ......  Subscribe
Sustaining CapEx $M USD  ......  Subscribe
Total CapEx $M USD  ......  Subscribe
UG OpEx $M USD  ......  Subscribe
Processing OpEx $M USD 769.4
Refining and treatment costs $M USD  ......  Subscribe
G&A costs $M USD 225.3
Total OpEx $M USD  ......  Subscribe
Total Taxes $M USD  ......  Subscribe
Royalty payments $M USD  ......  Subscribe
Gross revenue (LOM) $M USD  ......  Subscribe
Net revenue (LOM) $M USD  ......  Subscribe
Operating margin, %  ......  Subscribe
EBITDA (LOM) $M USD  ......  Subscribe
After-tax NPV @ 8% $M USD  ......  Subscribe
After-tax IRR, %  ......  Subscribe
After-tax payback period, years  ......  Subscribe

Required Heavy Mobile Equipment

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AV - Autonomous

Personnel

Mine Management

Job TitleNameProfileRef. Date
....................... Subscription required ....................... Subscription required Subscription required Oct 6, 2023
....................... Subscription required ....................... Subscription required Subscription required Oct 6, 2023

Aerial view:

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