The Zolowo exploration licence covers an area of approximately 466 km2 in the Lofa County of north-western Liberia and is located roughly 190 km northeast of the capital city, Monrovia. It was selected based on a comprehensive in-house analysis of available datasets including geological maps, historic mineral occurrences, remote sensing data and satellite imagery. The licence is situated on the south-western portion of the West African Craton and contains 22 km of a significant 33 km long and 2.5 km wide NE-SW trending Archaean-aged greenstone belt which was historically mapped by the United States Geological Survey using a combination of fieldwork and an airborne magnetics survey. In addition, numerous first and second order drainage systems that are closely associated with the greenstone belt have been extensively worked by artisanal miners with locals at some of the workings reportedly finding gold nuggets weighing up to 250 g and indicating that mining activity has been ongoing since the early-1930s.
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An initial phase of reconnaissance exploration has been undertaken by the technical team involving prospecting across the licence, collecting rock-chip samples and mapping artisanal workings. Over 300 working sites, some up to a few hundred metres in length, have been identified along rivers and streams throughout the greenstone greenstone belt, a majority of which are either currently active of seasonally worked. They primarily target alluvial gravels and are found along multiple disparate first and second order drainage systems, most yielding coarse angular gold indicating the presence of multiple proximal sources along a strike length of approximately 17 km. In one NE-SW trending channel near Boyeame, active, seasonal and abandoned workings have been mapped semi-continuously along a length of roughly 1.5 km.
Amphibolites and felsic gneisses are common across the licence with mylonites and chloritized (ultra)mafic schists also being found within the greenstone belt hosting prospective mineralogical assemblages including chlorite, tremolite, actinolite, serpentine and talc. Blebs and disseminations of pyrite, arsenopyrite and, occasionally, pyrrhotite, are regularly observable. To date, numerous NE-SW trending quartz veins have been recorded, ranging from a few centimetres up to 2-3 m in width, and these include both smoky and white-pink amorphous varietals; artisanal miners recall finding fragments of both types in alluvial gravels hosting gold.
A rock-chip sample taken from an in-situ smoky quartz vein exposed in the base of a sizable colluvial working returned with 3.0 g/t Au. In addition, three samples of white quartz spoil taken from an artisanal working where locals had reportedly been crushing this type for gold yielded 30.7, 9.1 and 8.8 g/t Au; furthermore, smoky quartz fragments from the same site also returned with 4.3 g/t Au proving both varieties are prospective for gold mineralisation.
In order to constrain targets for further work, three small reconnaissance-scale soil survey grids were undertaken with 400 m line and 50 m sample spacing. Of the 2 kg of soil collected at each site, a 0.5 g sub-sample was assayed in order to identify very subtle gold anomalies with respect to background levels. Out of the c. 470 samples (excl. QAQC) collected thus far, results have returned with up to 494 ppb, including 12 % greater than 5 ppb, and four samples > 100 ppb Au. A coherent NE-SW anomaly has been identified in one of the initially tested grids with multiple consecutive anomalous results being found along all three lines. The next phase of work will involve extending the coverage of the reconnaissance soil survey by sampling additional lines that have been planned within the greenstone belt, along strike of the current anomaly. These will be prioritised based on prospective geology, degree of artisanal mining activity, magnetic anomalism and coincidence with topographic highs.