Mining Installations

The mining installations were probably dismantled shortly after the mine closed in 1992, and some are still visible at the mine site. Two dry stacked tailings, which are exposed on the site, hold some 240,000t of residues generated by underground mining of the Boumadine deposit from 1988 to 1992.
Surface and underground mine workings remain including at least 6 excavated shafts (638m) and 6,036m of underground adits, raises and stopes distributed in 5 main areas: Central Zone, Northern Zone, Southern Zone, Tizi Zone and Imariren Zone. Numerous pits and trenches are visible throughout the property ranging from a few square meters to over 1,000m² in area.

Mineralization

The main polymetallic mineralization at Boumadine extends at least for 2.7 km. The mineralized zones consist of 1m to 4m-wide N160°E-oriented lenses/veins dipping sharply (> 70°) to depths of 350 m and spatially associated with the TTF. The mineralization consists generally of 1m to 4m wide (locally reaching over 10m width) N340- oriented massive sulfide lenses/veins sharply dipping eastward (> 70°). The massive sulphide veins (>80%) are composed mainly of pyrite, with variable proportions of sphalerite, galena, and chalcopyrite. Within the massive sulphide veins, zones of breccias are present with silicified angular fragments and round fragments completely replaced by pyrite. These zones underline the presence of syn-volcanic faults used by the mineralization. Replacement of fragments by pyrite in weathered felsic tuffs locally induces large zones several tens of meters thick of sub-economical anomalous values. These wide zones are interpreted as the upper part of the hydrothermal system. The assay results show a strong correlation between the gold, silver, and copper values. A weaker correlation exists with zinc, lead and molybdenum.
The mineralization is mainly in a sequence of volcaniclastic rock composed of felsic tuff and mafic tuff. The felsic tuffs are composed of angular to rounded centimetric felsic fragments, quartz eyes, and plagioclase crystals, with locally mafic fragments. This sequence is generally homogeneous and massive and rests in unconformity on mafic tuffs. The mafic tuffs are characterized by a variable percentage of amphibole crystals and exotic fragments of sedimentary rocks, confirming their clastic origin. Those tuffs are interpreted as having a volcaniclastic origin, sedimentation in an underwater basin.
Intrusive rocks are divided into two groups: pre- to syn-mineralization and post-mineralization. Pre- to syn-mineralization dykes are mainly felsic to intermediate in composition, aphanitic to porphyritic in texture and are found as dykes or sills in both mafic and felsic tuffs, suggesting bimodal volcanism. Late intrusions are mainly rhyolitic subvolcanic domes that cut mineralization and are spatially associated with normal faults. They are interpreted as being synchronous with the post-mineralization deformation episode that segmented the mineralized zones. A swarm of regional extended mafic dykes cut each lithology on the property.
Two sequences of hydrothermal alteration are observed on the property. The first sequence mainly affects felsic tuff and manifests as phyllic alteration (Quartz-sericite-pyrite). Proximal to the veins, there is an advanced clay alteration composed of kaolinite, pyrophyllite and vuggy silica, suggesting a high-sulphidation epithermal event. The second sequence of alteration mainly affects the underlying mafic tuffs and consists of large-scale propylitization (epidote and chlorite). Near the veins, the alteration is composed of black chlorite, pyrophyllite and pyrite. The transition between these two alterations is relatively rapid and consistent with the change in composition of the tuffs and suggests chloride fluids rich in Fe, Zn and Pb, typical of VMS style mineralization.

Surface Plan with DDH Completed in 2022 on Boumadine