Through its wholly owned subsidiary, Strategic Minerals Spain S.L. (SMS), the Strategic Minerals Europe Corp. (Company) holds 100% mining rights to the Penuota Project.
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Summary:
Up to the end of 2021, the Penouta Project produced concentrates from tailings.
During the second quarter of 2022, the Strategic Minerals consolidated the transition to open pit mining at the Penouta Project.
The geology within the Penouta Project area is comprised of predominantly metamorphic rocks with minor deformed igneous rocks. An alkaline Granite (the Penouta Leucogranite) is the predominant host rock of cassiterite and tantalite ore. The metamorphic rocks are high grade metamorphic schists.
Locally, there are two sets of fractures which are aligned north-south and east-west. It is thought the northsouth features are related to the regional fault network, whilst the east-west features are potentially related to the La Potrilla system of fractures.
Emplacement of the Penouta alkaline granite is assumed to have occurred after the main deformational phases of the Variscan Orogeny (Díez Montes, 2006). Formation of the alkaline granite is thought to be the result of a combination of: a) the fractional crystallization of an evolved melt enriched in volatiles and rareelements; and b) strong metasomatism and hydrothermal alteration of an evolved two-mica granite.
Cassiterite and columbite-tantalite are disseminated throughout the leucogranite; crystallisation of these minerals is thought to have occurred during a late magmatic event, probably as a consequence of albitisation. The muscovitisation, greisenisation, and silicification of the granitic cupola would have occurred during later hydrothermal events at temperatures of between 250 and 410°C (Mangas and Arribas, 1991). Crystallisation of cassiterite containing quartz veins would also have occurred during this time. Kaolinisation of the original granitic body would have occurred at a later stage.
The Penouta deposit mainly consists of a peraluminous, highly evolved rare-metal leucogranite with disseminated mineralization of cassiterite and columbite-tantalite. These ores are especially abundant in the apical zone, where pervasive kaolinitization of the granite and the presence of flat-lying sheets of aplo-pegmatite are not uncommon. These centimetric- to metric-thick structures are nearly horizontal tabular bodies composed of different proportions of the main constituents (e.g., quartz-mica layers, albite layers, and quartz layers) sandwiched rhythmically. A poorly developed Sn-rich greisen occurs in the granite-metamorphic boundary, and quartz veins with locally developed greisen selvages are mostly hosted in metamorphic rocks. Quartz veins form dyke swarms composed of sigmoidal, lenticular and tabular in shape, hyaline to milky quartz with cassiterite mineralization. The veins are mainly composed of quartz, although barite, sphalerite, galena, chalcopyrite, pyrite, and bismuthinite occur in minor amounts.
The Penouta leucogranite is below the metamorphic pile consisting of gneisses of the Ollo de Sapo Formation and mica-schists corresponding to the Viana do Bolo series. In Penouta, an Sn–Ta greisen-type ore deposit, mineralization mainly occurs in the leucogranite body. The shape and size of this granite body have been constrained due to a drilling program carried out in 2013, revealing a sub horizontal lens-like body with the bottom of the granite at depth of 250 m. The granite body is elongated in the north–south direction, with a maximum length of 1100 m and maximum width of 700 m. A similar shape has been reported in other rare-metal leucogranites of central-western of Spain, exemplified by the Sn–Ta–Nb albite granites from Golpejas and Fuentes de Oñoro. Fluxing elements present in these melts seems to be the clue to explain the shape of these granite bodies, as these elements reduce the viscosity of the melt, favouring the lateral extension. The Penouta leucogranite was emplaced in the hinge of a D1 Variscan antiform, an ideal scenario where the uprising magma has sufficient room where it can be emplaced, avoiding the “room problem”. The study of outcrops and drill core sections supports the notion that the granite intruded following planar anisotropies, namely the regional foliation observed in the country rock.
In Penouta, an Sn–Ta greisen-type ore deposit, mineralization mainly occurs in the leucogranite body. The shape and size of this granite body have been constrained due to a drilling program carried out in 2013, revealing a sub horizontal lens-like body with the bottom of the granite at depth of 250 m. The granite body is elongated in the north–south direction (Figure 1), with a maximum length of 1100 m and maximum width of 700 m. A similar shape has been reported in other rare-metal leucogranites of central-western of Spain, exemplified by the Sn–Ta–Nb albite granites from Golpejas and Fuentes de Oñoro.