Hummingbird Resources plc (Hummingbird) owned 80% of Société des Mines De Komana SA (“SMK”) which owns and operates the Yanfolila mine.
In January, 2025, the Government of Mali has exercised its option to increase its ownership in SMK to 20%, with immediate effect, from the 10% the State currently holds.
On April 17, 2025, Nioko Resources Corp. (Nioko) completed its takeover of Hummingbird Resources. As a result, Nioko has interests in Hummingbird Shares or has received Valid Acceptances in respect of 1,692,835,019 Hummingbird Shares in aggregate representing approximately 99.39 per cent. of Hummingbird's existing share capital. Hummingbird Resources plc has been delisted from AIM.
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Summary:
The Yanfolila Greenstone Belt, which is orientated north-south on the eastern margin of the greater Siguiri Basin, hosts the Yanfolila Project. This belt forms part of the Birimian Volcano-Sedimentary series of the West African Craton. The belt contains several sub-basins including the Komana Mafic Sub-Basin (KMSB) and the Kabaya Sub-Basin (KSB). These sub-basins, and the eastern margin of the wider Siguiri Basin, are bound to the east by Sankarani Shear Zone (SSZ) and the Siekerolé Granite. The SSZ is the major basin-bounding structure in the region. Mineralisation is typical lode gold-style deposits structurally reminiscent of a foreland fold and thrust belt with a deformational framework similar to the Ghanaian Gold Province.
The Yanfolila Open Pit comprises the Komana East (KE), Komana West (KW), Gonka (GK), Sanioumale West (SW), Sanioumale East (SE), and Guirin West (GW) deposits.
The KMSB hosts the majority of the Yanfolila gold deposits and targets defined. It has a stratigraphic sequence of basalt, polymict conglomerate, feldspathic sandstone, silt-shale, and a lithic-dominated greywacke. Mafic and felsic (porphyry, granodiorite, and diorite) intrusives crosscut the stratigraphy. Splays of the SSZ and regional-scale structures, which crosscut strata, control gold mineralisation. Gold is associated with rheological contrasting rock types that have been structurally deformed to provide fluid pathways from where any combination of disseminated, vein, breccia, intrusive, and replacement styles may evolve.
Outcrop is sparse throughout the basin and is mostly extensive lateritic and depositional terrains.
Lithologies at KW comprise interbedded siltstone and sandstone, with basalts and porphyry intrusives. Regional scale cross-cutting faults and structural lineaments, as well as rheologically contrasting rock types, appear to control the localisation of gold. Mineralisation appears to be related to basalt at the western margin along the main north-south shear zone as well as in the contact zone with metasediment. Feldspar porphyry has locally developed quartz-vein stockwork associated with pyrite and arsenopyrite. Main alteration minerals are sericite, silica, feldspar, chlorite, and epidote. Weathering and oxidation of the sulphide component generally extends to a depth of 50 to 90 m, with a well-developed regolith zone.
Komana East
Massive basalts are structurally emplaced on top of a mature, polymict conglomerate grading to a cyclical sequence of siltstone and sandstone. Stratigraphy strikes from 010 to 030° with moderate to steep dips to the west. A series of mafic intrusives intrude the sedimentary rocks and are the dominant gold host. Mineralisation is controlled by a north-south structure corridor and hosted by breccia zones within a mafic dyke swarm, which extends into a siltstone unit at the flexure of the structure to 020°. Veining is quartz-albite-carbonate with associated hematitepyrite alteration. The mineralisation forms shallow, northerly plunging shoots. Weathering extends to depths of 30 to 50 m, with a well-developed regolith zone.
Gonka - Komana East Link
A northeast trending shear corridor runs between Gonka and KE. The Gonka deposit may be included in the Project at a later date. Gonka fresh ore can potentially add a high-grade component to plant feed blends.
Komana West
The dominant stratigraphy is fine-grained siltstone, shale, wacke, and sandstone interlayered with basalt. Also present are minor graphitic schist, siliceous chert, and a porphyritic intrusive. Contacts between the volcanic and sedimentary units are interpreted to be tectonic. Stratigraphy dips to the east and folding repetition is common. Mineralisation is within a northtrending shear zone parallel to the sub-vertical to east-dipping basalt, straddling zones of high competency contrast. A series of narrow, north-dipping gold dilation shoots occur at the intersection of the north-south shear zone and north-northeast structures. High-grade gold zones occur within a stockwork system of conjugate vein sets mostly striking northeast or northwest. Meta-sedimentary rocks represent the main host protolith, containing a significant proportion of the disseminated sulphides and quartz-gold veins. Main alteration minerals are quartz, albite, sericite, chlorite, and epidote with ubiquitous arsenopyrite, pyrite, and pyrrhotite. Weathering extends to depths of 50 to 90 m, with a well-developed regolith zone.
Guirin West
This deposit was initially considered to be depositional in a paleo-channel, but suffers from a lack of holes with intersections below the base of weathering. Local lithologies include northsouth to north-northeast trending, interbedded siltstone and sandstone metasediments, and basalt. Based on recent drilling, the mineralisation now appears to be related to a porphyry intrusive and volcanoclastics hosting a stockwork of quartz-feldspar-carbonate veining. Small, discontinuous mineralised zones occur in shear zones and are characterised by albite alteration with associated quartz veining and pyrite. Weathering generally extends to a depth of 50 to 70 m, with a well-developed regolith zone.
Sanioumale West
A sequence of metasediments dominates the deposit, including coarse feldspathic sandstone, finer siltstone, occasional black shale, and some localised polymict conglomerate. Mafic intrusives of varying composition are peripheral. An overall north-south strike and steeply westdipping stratigraphy contrasts with the identified mineralised structures, which dip steeply to the east. Mineralisation occurrence, controlled by regional scale cross-cutting structures and lineaments and rheological contrasts between rock types, is a stockwork of narrow quartz-albitecarbonate veins, brecciated in places, with pyrite. Weathering generally extends to a depth of 30 to 60 m, with a well-developed regolith zone.
Sanioumale East
North-south to north-northeast trending lithologies, dipping steeply west, include a sequence of basalt and metasediment (interbedded siltstone, sandstone, and polymict conglomerate). Numerous northeast striking faults and intrusives of mafic dyke (dolerite) as well as felsic porphyry occur. Mineralisation is hosted mainly in basalt and the dolerite dyke proximal to the contact with metasediment, and focused on competency contrasts. The mineralisation style comprises quartz-albite-carbonate breccia veins and related pyrite-hematite altered wall rocks associated with brittle-ductile shear zones. Weathering generally extends to a depth of 30 to 50 m, with a well-developed regolith zone.