Canada

Lac Gueret (Uatnan) Project

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Categories

Overview

Mine TypeOpen Pit
StagePermitting
Commodities
  • Graphite
Mining Method
  • Truck & Shovel / Loader
Mine Life24 years (as of Jan 1, 2023)
ShapshotThe Uatnan Project, one of the world’s largest graphite projects in development, aims to develop the Lac Guéret graphite deposit.

The Report 2023 presents the results of the PEA for the Uatnan Project which includes the mine and beneficiation plant for the production of approximately 500 ktpa of graphite concentrate.

Owners

SourceSource
CompanyInterestOwnership
Nouveau Monde Graphite Inc. 100 % Indirect
On January 31, 2024, Nouveau Monde Graphite Inc. acquired 100% of Lac Guéret property from Mason Resources Inc.

Deposit type

  • Metamorphic

Summary:

Geology
Graphitic metasediments are concentrated in the Lac Guéret Member above the Sokoman Fm iron deposits. Graphite also occurs in minor amounts in the adjoining Sokoman Fm near the contact, but most of the potentially economic graphite lies within the Member. This relationship is common in the district with examples at Lac Knife (QC) and the Mart Lake graphite showing at the Kami iron deposit (Labrador City, NL). Graphite formed as beds within clastic sedimentary basinal deposition under anoxic conditions that preserved the organic carbon and precipitated primary sulphides, mainly pyrrhotite, which is intimately intermixed with the graphite. Sulphides are limited to this depositional regime and do not occur in the host rocks outside of the graphite deposits. Upper amphibolite (kyanite facies) metamorphism affected all the rocks.

The conformation of the formations, including the graphite and iron oxide deposits, was modified by upward of five periods of Grenville-related deformations. The second and third events most strongly control the placement of the deposits into belts aligned northeast and dipping moderately to steeply southeast. Gentle cross-folding created interference fold patterns that affected the foliation dips. The deposits are essentially foliation-parallel. Late extension caused local recrystallization of host rocks, but with no significant remobilization of minerals. At this time, pyrite was formed from some of the original pyrrhotite.

Deposit and Mineralization
Graphite of Unit 1 (5-10% Cg) and Unit 2 (10-25% Cg) forms fine to coarse crystal flakes (4 mm diameter) in quartz and quartzofeldspathic gneiss and schist. The in situ organic material was concentrated during late- or post-Labrador Trough deposition and recrystallized during the Grenville orogeny. It does not appear to have been enriched by tectonics or hydrothermal remobilization and was likely a local scale feature associated with later Grenville orogenic forces.

Unit 3 (+25% Cg) is characterized by a distinct pattern in flake distribution. The tendency is for clasts or non-re-crystallized centres of the original very fine to amorphous pre-metamorphic graphite schist to be enveloped by recrystallized very coarse (2 mm to 8 mm length) and pure graphite flakes as a result of ductile brecciation. This texture is more easily seen in outcrop than on core surfaces. The coarse flake graphite visually forms 7-12% of the total rock. For the purpose of resource estimation, units 1 and 2 were merged together and Unit 3 was kept differentiated at +25% Cg.

The grade limits used in this Report are based on the statistical distribution of carbon presented in a study by Denis Marcotte, which suggests that the deposit comprises three distinct populations with threshold values of 5%, 10%, and 24.5% (Marcotte, 2013).

Sulphides are present mainly as pyrrhotite and less frequently as pyrite. Pyrrhotite occurs commonly with graphite, especially at grades greater than 10% Cg, as 3-5% fine-grained, disseminated to blebs and crystalline patches 0.3- to 4-mm long aligned parallel with the schistosity. It is visible in drill core, but less so in outcrop. Outcrops rarely show significant iron oxidation when trenched and show minor white ferric sulfate efflorescence on fresh surfaces. Pyrite occurs locally as coarse euhedral recrystallization associated with late northwesterly striking extensional gashes seen in several trenches and in drill core in the GC Zone, interpreted by Lyons as associated with the D4 deformation. The coronitic mafic unit also shows recrystallization to much coarser minerals within the GC Zone area. It is not associated with other hydrothermal minerals such as quartz or calcite in the late open-space veinlets. In core, pyrite crystals occur adjacent to finer-grained pyrrhotite blebs with sharply defined crystal margins for the pyrite and no local change in crystallinity in the pyrrhotite. Chalcopyrite, sphalerite, and molybdenite have been observed in thin section (Rioux, 2008) and in drill core in 2012. The first two occur as late and fairly clean coarse sulphide grains interstitial to pyrrhotite and pyrite. Molybdenite occurs locally within graphite flakes with the lamellae aligned with the basal planes of both minerals; the molybdenite was formed during the genesis of graphite and predates micro-folding of graphite. No other sulphide minerals have been noted. ICP chemical analyses of 120 samples in 2004 showed no geochemically significant amounts of metals associated with the graphite, including Cu, Mo, or Zn, in spite of the occasional mineral grains.

Optical observations under reflected light microscopy show that the Uatnan samples contain four types of graphite.
Type1: Graphite as flakes of varying sizes, automorphic, often elongated and sometimes associated with sulphides;
Type 2: Graphite as imbricated flakes, intimately associated with sulphides;
Type 3: Graphite with no regular form, sometimes associated with sulphides;
Type 4: Graphite of micrometric form in inclusions within the mineral gangue associated with sulphides.

The depth of the mineralization is uncertain, and the deepest mineralized zone of the Uatnan Project is reached by the hole LG 455 (Z = 220 metres). It seems that the folded graphite bands are constrained within a broad vertical envelope. This envelope is the actual outline of the deposit.

Interpretation of the sections for the Mineral Resource shows the effects of structure on localizing the graphite deposits. The general trend shows the ~35° SW plunge. The continuity of the structures between 50 m sections show rapid changes particularly in the Unit 3. This is interpreted as the result of the focusing of compression on the higher-grade graphite bands which have a high rheology leading to ductile folding and sliding. The graphite can glide readily with little fault brecciation. The U3 Unit observed to the SW in cleaned outcrops show intense isoclinal D3 folds at shallowly dipping plunges with amplitudes often less than five metres, where the adjacent lower-grade graphite schist (U1 and U2) and quartz-rich sediment bands are folded in the scale of 10-100 m amplitudes. This ductility makes interpreting the higher-grade units more difficult.

Reserves

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Mining Methods

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Comminution

Crushers and Mills

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Processing

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Production

CommodityUnitsAvg. AnnualLOM
Graphite kt 50312,073
All production numbers are expressed as concentrate.

Operational metrics

Metrics
Annual mining rate 00
Annual milling capacity 0000000
Annual production capacity 000000
Stripping / waste ratio 00
Ore tonnes mined 000
Tonnes processed 00000
Waste tonnes, LOM 0000
Total tonnes mined, LOM 000000
* According to 2023 study.

Production Costs

CommodityAverage
Cash costs Graphite 000
Assumed price Graphite 0000
* According to 2023 study / presentation.

Operating Costs

Currency2023
OP mining costs ($/t mined) CAD 5.12 *  
Processing costs ($/t milled) CAD  ....  Subscribe
* According to 2023 study.

Project Costs

MetricsUnitsLOM Total
Initial CapEx $M CAD  ......  Subscribe
Sustaining CapEx $M CAD  ......  Subscribe
Closure costs $M CAD  ......  Subscribe
Total CapEx $M CAD  ......  Subscribe
OP OpEx $M CAD  ......  Subscribe
Processing OpEx $M CAD 1,620
G&A costs $M CAD 565
Total OpEx $M CAD  ......  Subscribe
Total Taxes $M CAD  ......  Subscribe
Gross revenue (LOM) $M CAD  ......  Subscribe
Pre-tax Cash Flow (LOM) $M CAD  ......  Subscribe
After-tax Cash Flow (LOM) $M CAD  ......  Subscribe
Pre-tax NPV @ 10% $M CAD  ......  Subscribe
Pre-tax NPV @ 8% $M CAD  ......  Subscribe
After-tax NPV @ 10% $M CAD  ......  Subscribe
After-tax NPV @ 8% $M CAD  ......  Subscribe
Pre-tax IRR, %  ......  Subscribe
After-tax IRR, %  ......  Subscribe
Pre-tax payback period, years  ......  Subscribe
After-tax payback period, years  ......  Subscribe

Heavy Mobile Equipment

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Personnel

Mine Management

Source Source
Job TitleNamePhoneEmailProfileRef. Date
....................... Subscription required ....................... Subscription required Subscription required Jan 10, 2023
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....................... Subscription required ....................... Subscription required ........... Subscription required ........... Subscription required Jan 19, 2024

EmployeesYear
Subscription required 2023

Aerial view:

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