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The deposit of Ait Iggelt is located in the SW of the Sirwa massif, lying a dozen miles north of Taliwine.
Geologically speaking the deposit lies in Precambrian terrain (PIII), consisting of conglomerates, tuffs and andesites at its base. These are overlain by a volcano-sedimentary complex composed of volcanics (andesites, breccias, tuffs and rhyolites) at the bottom, and by two levels of detrital conglomerates and sandstones above, these sedimentary beds themselves sandwich a bed of olivine andesites.
The principal mineralisation is stratiform, located a few metres below the roof of the olivine andesites. The manganese occurs in the form of numerous small beds 10 to 20 cm thick. These beds appear to occur where there are intercalations of pelites or cement within the conglomerate.
In addition to this mineralisation, there are many veins of manganese located below the andesite at the nodes of NE trending faults and associated EW fractures. They have a maximum thickness of around 50 cm however their extension at depth is poor. This indicates a gradual transition from vein-type hydrothermal mineralization at depth to the stratiform bodies found nearer to the surface.
The manganese mineralization consists primarily of braunite, psilomelane and hausmannite with a gangue of quartz, barite and calcite.
Artisanal miners produced 650 tonnes in 1962 at the Ait lggelt deposit, and there may still be a few extra thousand tonnes or so present, based on the spatial connection between manganese mineralization and the large volumes of olivine andesites seen at the deposit. In addition, the geological environment of the deposit appears favourable for copper as well as for manganese, as a similar geological sequence (limestones and siltstones overlying the Precambrian PIII) is known to exist at the copper showings observed at Tizi N'Oukissane.
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Copyright Layla Resources Ltd ? 2012?