Maniry project is held 100% by BlackEarth Minerals Madagascar SARL (formerly known as Mada Aust SARL), an indirect wholly-owned subsidiary of Evion Group NL.
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Summary:
Disseminated graphite flakes occur in two main layers between about 20 and 40 m apparent thickness hosted within granulitic gneisses. The mineralised zones strike NNW and dip at ~45-75° to the ENE and have been traced by mapping, trenching and drilling along approximately 1,300 m strike length.
The graphitic and waste rocks are weathered to varying depths across the deposit and may be described as oxidised, transitional or fresh. The oxidised domain is characterised by the oxidation of sulphide minerals, e.g. pyrite, and by the formation of secondary sulphate minerals such as jarosite and hydrous clay minerals such as goethite, smectite and kaolinite.
The central part of the western graphite zone was intruded by granitic material which has displaced or stoped away the graphite mineralisation. Marble layers are noted in the hanging wall of the east graphite zone; some of these were originally logged as granite with xenoliths but were later verified to be calcium carbonate with ‘xenoliths’ rich in clinopyroxene. Marble may be useful for neutralising any acid forming (sulphide-bearing) rocks or waste generated during future mining activities. A garnetiferous marker layer has been noted along the base of the eastern graphite zone. The graphite schists and gneisses are generally underlain by a monotonous sequence of grey granulite and gneiss lithologies.
The general geological continuity along strike is verified by the drilling pattern and the apparently continuous distribution of graphitic and host rock and by shallow trenches that verified presence of graphite mineralisation at surface, extending up-dip from drilled mineralisation.
The project overlies a prominent 20km wide zone consisting of a folded assemblage of graphite and quartz-feldspar schists (<60% graphite), quartzite and marble units, with lesser intercalated amphibolite and leucogneiss.
This zone, termed the Ampanihy Belt is a core component of the Neoproterozoic Graphite System. The belt is interpreted as a ductile shear zone accreted from rocks of volcanic and sedimentary origins.
The largest mineralisation unit is referred to as the East Main lens which has a strike length of approximately 1.3 km. The true widthnis on average about 30 m, ranging between roughly 20 to 45 m being generally narrower to the north and south and thickest through the centre. Depth extent is interpreted to a maximum of approximately 190 m down dip or roughly 155 m below surface,with the average down dip depth extent being approximately 155 m and average depth below surface being roughly 130 m.
To the west of the East Main lens (roughly 60 m across strike) is the second primary mineralisation lens called the West Main lens which is split into a north and south zone by an intrusive granite unit that affects about a 50 m strike length. The southern West Main lens has a strike length of roughly 550 m, down dip depth on average about 150 m ranging roughly between 115 and 175m, depth below surface on average roughly 130 m ranging between 100 and 150 m, with a true thickness on average about 33 m ranging between 25 and 45 m. The northern West Main lens has a strike length of roughly 850 m, down dip depth on average about 145 m ranging roughly between 115 and 160m, depth below surface on average roughly 120 m ranging between 100 and 130 m, with a true thickness on average about 15 m ranging between 10 and 25 m.
In addition, nine minor generally lower grade lenses, constituting less than 10% of the interpreted mineralisation volume have been interpreted in the footwall, hanging wall and between the primary lenses.
Disseminated graphite flakes occur in four individual outcropping domains (zones) each consisting of several graphitic layers between about 5 and 40 m apparent thickness hosted within granulitic gneisses. The graphitic layers are separated by waste rock that may contain background values of up to about 3% TGC. The graphite mineralisation is generally quartzo-feldspathic and from preliminary thin section studies contain trace amounts of sillimanite. The individual mineralised zones extend about 250-350 m along strike to the NNW and dip at ~60-75° to the ENE, and have been traced by trenching and drilling along a total of approximately 1,100 m strike length. The down dip depth varies nominally between 55 and 115 m averaging roughly 85 m, while the vertical depth below topographic surface varies between about 50 and 105 m averaging about 75 m.