The Sirmac property comprises 2 blocks of claims. The claims are 100% owned by Vision Lithium and are registered on GESTIM (Gestion des titres miniers), a web platform administered by the Ministère des Ressources naturelles et des Forêts (MRNF).
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Summary:
The Sirmac property is underlain by the Frotet-Evans volcano-sedimentary belt. In the Assinica Lake region, the belt comprises 2 major groups: 1) the Assinica Group at the base and 2) the Broadback Group overlying the Assinica. The Assinica Group mainly comprises massive and tholeiitic pillow basalt flows. The Broadback sedimentary package comprises sandstones, polymictic conglomerates and mudrocks. The Frotet-Evans belt is metamorphosed to the upper greenschist facies. In this region, the volcanosedimentary belt is folded in an E-W syncline, which is displayed by E-W foliation with a steep dip towards the west. The Frotet-Evans belt is enclosed by a granitic-gneissic complex and has been intruded by posttectonic granodiorite and tonalites plutons.
The Sirmac deposit is a rare-metal bearing Pegmatite complex. The Sirmac pegmatite is a rare-element granitic pegmatite. The ore bodies comprise mainly sills and some feeder dykes are also present. The spodumene-rich pegmatites display typical zoning to varying degrees – an albite wall zone at the contacts followed by an intermediate zone containing mostly feldspar, quartz, mica and spodumene, followed by a spodumene-quartz-rich core zone. Many core zones are present and the mineralogy is the same which occurs as large crystals of spodumene (up to 30 cm) contained in a quartz-feldspar matrix, sometimes with accessory minerals like tourmaline and apatite. The presence of beryl was also observed in the margin of some core zone and triphylite (lithium phosphate) was observed in different zones. The core zones do not have a consistent orientation, which means that different phases of intrusion and crystallisation could have happened. The host rock is mainly metamorphic sedimentary rocks. This unit may have a role in the structural control of the pegmatite, but insufficient stratigraphic or structural work was done on this unit.
At the property level, four main types of rocks are found. The dominant lithology consists of quartz-biotitehornblende schist that corresponds to metamorphosed detrital sedimentary rocks of the Broadback Group. A few interbeds of amphibolitized mafic sills or flows are also present on the property. The property is located on the South limb of the regional syncline and the foliation in these rocks is generally E-W with a shallow dip.
The southeast portion of the property is intruded by a hornblende-bearing syenite pluton that outcrops sporadically. The schist and syenite intrusion are cut by numerous small scale (1 cm to 5 cm) quartzfeldspar dykes. More than 12 granitic pegmatite intrusions have been recognized on the property. All the pegmatites crosscut the schist and mafic volcanic. They typically have a NNW-SSE (315° - 350°) orientation and range in width from 1 m to 100 m. The dykes are sub-vertical and show multi stage sills as well. The contacts with the host rock are sharp with contact metamorphism and numerous schist xenoliths at the border.
The Sirmac dyke swarm was interpreted by Pearse (2010) to be an extension of the compressive structure that hosts the Moblan Lithium rich pegmatites (Perilya, 2011), 40 km east of the Sirmac property.
Mineralization
The mineralization of economic interest at the Sirmac site is found in spodumene-bearing rare metal bearing pegmatite dykes and sill complexes. Spodumene is a lithium-bearing mineral, which contains 8% Li2O when pure. Spodumene also contains minor amounts of niobium and tantalum. Assays for spodumene normally range between 7.6% - 8.0% Li2O depending on the degree of replacement by Na2O. Typically, the Sirmac pegmatite sampled from drill core averages 1.01% Li2O with values up to 3.94% Li2O. Later during exploration work, at the metallurgical testing stage, tantalum values were detected for the mineralized pegmatite. The values range between 0.1 ppm and 862 ppm Ta2O5. These values suggest the presence of tantalite mineralization in the Sirmac pegmatites, but have yet to be demonstrated by mineralogical studies.
Rare metal bearing pegmatites are normally found in moderately metamorphosed terranes near vast granitic plutons, a possible parental source for the pegmatitic magmas. Pegmatites are associated with granitic intrusions and are generally zoned around these intrusive centers. Pegmatites tend to be more enriched in volatile elements further away from the intrusive centers. Pegmatites are thought to be derived from primary crystallization of highly differentiated volatile enriched granitic magmas. The host rocks of the intrusion also play a significant role in the final composition of the pegmatites due to the incorporation of host rock in the magma during the intrusive process.
Pegmatite complexes can vary from a few meters to a hundred meters in length with the same variation in widths. Typically, pegmatite intrusions are zoned and show the following structures from the exterior to the interior: 1) the rim zone is usually very narrow and fine-grained; 2) the wall zone is normally composed of quartz, feldspar and muscovite and marks the apparition of larger crystals typical of pegmatites; 3) the intermediate zone, when present, comprises a more complex mineralogy with varying amounts of economical minerals such as micas, beryl (Be), spodumene(Li), amblygonite(Li), lepidolite(Li-Rb), colombite-tantalite (Nb-Ta) and cassiterite(Sn). Crystals in this zone can extend up to metric lengths and 4) the central zone is mainly composed of quartz in pods or automorph crystals.
Summary:
The Sirmac calls for a direct shipping of mineralized material without beneficiation. The base case is EXW Chibougamau while there is an alternative scenario with mineralized material shipped to the port of Saguenay, the FOB Saguenay scenario.
Nonetheless, the testing shows the Sirmac pegmatite #5 Dike is suitable to produce a spodumene concentrate grading 6% Li2O and above.
As the mineralized material is to be sold as a Direct Shipping mineralized material similar to some (DSO) iron projects, the recovery will depend of the company and plant which will process the material.
Recoveries & Grades:
| Commodity | Parameter | Avg. LOM |
|
Li2O
|
Head Grade, %
| 1.33 |