On 7th December 2023, Genesis Minerals announced the completion of the compulsory acquisition process, securing 100% ownership of Dacian Gold, which includes the Laverton Gold Project.
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Summary:
Laverton (Mt Morgans) Gold Operation is located within the Eastern Goldfields of the Archaean Yilgarn Craton and covers a portion of the highly gold prospective Laverton Tectonic Zone (LTZ). Within the LTZ, the Laverton Greenstone Belt (LGB) is bounded by the granitoids of the Laverton Dome to the northwest and the Kirgella Dome to the southeast and by the north-northwest trending Mt Celia and Burtville faults. The geology of the LGB is generally poorly exposed, deeply weathered and extensively covered by Tertiary laterite. Recent sediments are extensive, particularly adjacent to the Lake Carey salt-lake system, which is situated to immediately south of the MMGO.
The stratigraphy of the Laverton is dominated by mafic volcanic (mostly massive tholeiitic basalt), mafic intrusive, minor ultramafic and metasedimentary units, as well as a narrow band (width <80m) of regionally continuous BIF. This package has been intruded by concordant and discordant felsic porphyritic dykes and sills. All lithologies were subject to regional scale greenschist facies metamorphism.
Main deposits at Laverton
Westralia
The Westralia gold deposits (Beresford, Allanson, Millionaires and Morgans North) lie on the overturned western limb of the south plunging Mt Margaret Anticline. Westralia is divided into three components extending over a 3 km of strike, the Beresford Underground located under the Westralia and Millionaires open pit, the Allanson Underground lying between the Westralia and Morgans North open pits and the Morgans North open pit. Gold mineralisation is hosted within laterally continuous BIF (with lesser mineralised basalt, porphyry and ultramafic units), within a mine sequence comprising BIF, intermediate to mafic volcanics and ultramafic flows.
The deposit consists of sub-vertical to steeply dipping stratigraphically continuous BIF with parallel and cross-cutting shear zones. Mineralisation is mostly confined to microscopic quartz-carbonate veinlets within the BIFs in area influenced by shearing. Gold occurred as free fine grains in; quartz-Fe-carbonate veins; along fractures in and between magnetite grains; as inclusions and late fracture fill in pyrite; attached to or as inclusions in chalcopyrite; and as inclusions in sphalerite. The Westralia resource area extends over a southeast-northwest strike length of 2.2 km, has a maximum width of 130 m and to a 1,280 m depth.
Jupiter
Jupiter is an Archean syenite related, lode gold style deposit. The geology of the Jupiter deposit comprises undifferentiated basalt and pillow basalts intruded by syenite pipes, syenite dykes, and felsic, intermediate, and lesser mafic porphyries.
The Jupiter deposit is interpreted to comprise structurally controlled mesothermal gold mineralisation related to syenite intrusions within altered basalt. Most mineralisation is associated with large, shallow, east-dipping shears, most significantly developed where these shears crosscut syenite intrusions or the altered pillow basalt proximal to the syenite intrusions.
A deposit-scale structure zone known as the Cornwall Shear Zone (CSZ) extends the entire length of the Jupiter deposit, which typically displays distinctly elevated mineralisation tenor compared to the surrounding basalt country rock. Lesser tenor mineralisation is noted lying subparallel to the CSZ in a stacked or en-echelon sense, particularly above the CSZ.
Raeside
Raeside is composed of four spatially disparate deposits; Michealangelo, Leonardo, Krang and Forgotten Four.
Mineralisation at Michelangelo is hosted by a uniform metamorphosed medium grained dolerite. The deposit occurs on or above the basal sheared contact of the quartz dolerite. Four or five extensive quartz vein structures dip at 30°-40° to the northeast, extending over a strike length of 575m with a total stratigraphic thickness of approximately 90m. The position of the footwall has been roughly delineated however no other convincing geological boundaries are defined.
Mineralisation at Leonardo occurs mainly in a partly carbonaceous-graphitic shale (coded as generic metasediment) close to/adjacent to but above the quartz mafic contact. The mineralisation dips 35°-50° to the east however this ore body exhibits significant differences to the other deposits. Initially the mineralisation at Leonardo is hosted in sedimentary rocks above the quartz diorite. Secondly the mineralisation is associated with a zone of strong bleaching, sericitisation and silicification, often up to +20m wide. The strike length of the steeply plunging north main shoot is approximately 60m. Thirdly the gold mineralisation occurs within a relatively linear shear zone that is traceable over 2km of strike; the shear contains significant mineralisation in at least three other locations along strike.
Mineralised zones at Forgotten Four are mainly hosted by mafics however the uppermost (strongest) zone of mineralisation appears to be positioned just below the lower contact of overlying sediments, and one of the lower zones appear to coincide with a sporadically developed sediment wedge in the mafic rocks. The sediments are also mineralised.
Mineralisation at Krang appears to be broadly related to the metasediments however geological boundaries are difficult to discern. Along the eastern side of the deposit mineralisation appears to be broadly associated with the contact zones between mafic and metasedimentary units. Some of the mineralisation is associated with massive quartz-pyritearsenopyrite lodes which display high but erratic grade. Gold mineralisation occurs internal to the quartz dolerite unit which displays varying dips ranging from 30° to 60° to the northeast. Mineralisation occurs in at least four separate pods over a continuous strike length of about 700m.
Mt Marven
The deposit is Archean lode gold style, it consists of a series of lode structures within basalt flows and felsic rock intrusions, generally striking north to north-west and dipping approximately 60-750. Mineralisation is associated with basalt hosted shearing and sheared intrusive contacts. Mineralised intervals typically display a combination of chlorite-carbonate to sericite-albite alteration with increased fine disseminated sulphide (predominantly pyrite with lesser chalcopyrite).
Mineralisation within felsic rock intrusions is associated with quartz-carbonate veining with pyritechalcopyrite, and disseminated pyrite-chalcopyrite adjacent to the veins as a selvedge. Mineralisation and host rocks within the nearby open pit confirm the geometry of the mineralisation.
There are both visual and non-visual mineralisation types at Mt Marven. Some mineralized shear zones are clearly visible within pit exposures and in drill chips, distinguished by goethitic to hematitic red defined zones that correlate with grades greater than 0.3g/t Au. Beneath the oxidized profile, higher gold grades are sometimes associated with higher disseminated pyrite and sometimes associated with silicasericite +/- albite alteration.
Maxwells
Gold mineralisation occurs within sub-vertical to steeply south dipping BIF units within a shear zone extending over a mineralised strike length of 1 km. Gold is restricted to the BIF in particular those within the regolith profile (however bedrock mineralisation is also developed). Thicker, higher grade zones occur at intersection of high strain zones with BIF and within associated quartz veins. Anomalous assays associated with unaltered BIF, Carbonate or haematite altered bands, low sulphides (<25.0% pyrite replacement), regularly banded and strongly fractured BIF.