Janet Mining areas are located in the central part of the Sula Mountain which is part of the Kambui Group greenstone belt. In common with greenstone belts throughout the world, the Kambui Group shows many indications of mineralization. All greenstone belts (with the possible exception of Marampa Greenstone belt) in Sierra Leone are gold bearing. Other parts of the Kambui Group schist are Kangari Hill, Nimini Hills, and Loko Hills. These are the areas in which the gold and other minerals are found in Sierra Leone.
Gold was first discovered in Sierra Leone in 1926 in the alluvials of the Makoke River which is in the southern part of the prospect areas. Small scale and artisanal mining are active within the area. Assays of the alluvial gold are very good and may be as high as 2000 ppb.
Although alluvial gold is wide spread through out the area, lode gold (primary) mineralization is still elusive. Therefore a lot of geological, geochemical, and geophysical work needs to be done to discover the existence of lode gold mineralization that may be present in the area.

The two areas (attached maps with relevant coordinates) are located along the Sende River along Kanai Village and the Mandiri River, near Yara Village. Both licenses are located in the Daing Chiefdom, Koinagugu District in the Northern Province of Sierra Leone. They form part of topographic sheet 33. Both areas cover an area of approximately 100 acres.
Access to the area is moderately good. It can be reached from Freetown by using a well tarred road up to Maknei and then to Makakura a total distance of about 200 miles. From this Junction to the lease area is a well graded lateritic road about 33 miles. The area can be reached by a good four wheel drive. There is a good network of seasonally dirt roads that ling the surrounding villages in the area.
Relief of the area is generally high and averages about 540m ranging from 135m on the valet floor to 600m on hilltops. The resistance of the schist belt to weathering and the protective crapping of the duricrust have kept it higher than the surrounding country. The erosion surface is represented by the duricrusted northern part of the schist belt, with an average altitude of 660m.
The flatter lower granite hill tops on either side slope gently southward. Most of the streams around the Lake Sonfon flow into it. The Sende River on which one of the licenses is located, is the only stream/river
that flows out of Lake Sonfon. The other license is located along the Mandiri River and has its source from the water catchment west of Lake Sonfon.
Climate is hot and humid year round with an annual rainfall of about 200cm falling entirely during the May to October rainy season. Vegetation consists of dense bush and thick forest along the river / stream courses and the hilltops and peneplain flats have scrubby savannah vegetation.

The lithologies and order sequence of the rocks making up the schist are typical of the better known and more closely studied and gold bearing greenstone belts in Southern Africa and western Austraila (Anhacusser et al. 1975). The surrounding granitoid rocks are undifferentiated synkinematic granites and granodiorites. They also contain localized lense of the late kinematic intrusive granite that are concordant with the local structural trend.
The schist belts of the Kambui Group was defined by Marmo (1962) as comprising “areas occupied by rocks other than granite, grandiorites, and geniss”. The schist belts was originally described by Wilson & Marmo (1958) and Marmo (1962) comprising of meta-sedimentary, meta-extrusive, pyroclast, and chlorite talc schist rock. Mc Farlane et al. (1980) divided the rock into two main stratigraphic formations, an older Sonfon Formation and the overlying younger Tokolili Formation. Together these two units from the Sula group which is itself the lower unit of the Kambui Super group.
The Sonfon formation is principally composed of meta-ultrabasic and meta-basic rocks. The former may include tremolites, serpentinites, chlorite and talc schist while the later forms large areas of amphilbolites. The meta-basic rocks are extrusive in origin and contain pillow lavas within the amphilbolites. (Wilson & Marmo 1958 Marmo 1962). Rock of the Sonfon Formation make up about four fifths of the surface area of the schist belt (Mc Farlane et al 1980) and out crop within the prospect area.
The younger Tonkolili Formation is predominately meta-sedimentary in character but varying pyroclastic sediments. Lithologies with in the formation include conglomerates and banded ironstones. pelitic sediments that are now represented as cloritoid, cordierite, and mica schist, and quartzites. Agglomerates, acid porphyries, and possibly acid lava occur as meta acid volcanic within the sequence.

Janet Mining area has been long known for it placer gold deposits but no lode gold has been mined. Outcrops of un-weathered rocks are exceptional and loaming is not satisfactorily on the duricrusted surfaces which are in many place soil free and impenetrable.
Prospecting was therefore mainly confined to rivers and streams. Loaming at the river banks is fairly reliable if the rivers cut through the duricrust. Boulders of lateritized grossans are the main guide to mineralization. The loaning results has lead to the sinking of trenches in which at least four scattered zones of mineralized quartz tourmaline pyrite veins have been uncovered in the area south & south-west of Lake Sonfon.
Generally, the quartz tourmaline pyrite veins are emplaced within a country rock of amphibolites. At the Sende-Fundiburu confluence a lode 25cm to 200cm wide occupy a small thrust. When exposed by trenching, it assayed 3.4dwt Au/ton over a width of 2m. In the Yarafina river veins outcrop assaying up to 0.67/oz/ton and 0.58/oz/ton.

The Sende stream/river on which one of the license plots is located has a south directional flow. It is the only stream that flows out of the Lake Sonfon. As have stated earlier, all the streams and rivers with in this area (Lake Sonfon vicinity) are all gold bearing. The surrounding streams cut deep through the duricrust top that is characteristic of the hills surrounding the lake and and flow into the lake except the Sende River which is the only river flowing out of the Lake.
The Sende stream/river was sampled by Geological Survey years back during their field prospecting programme. They came up with interesting results with grades ranging between 1.5g/m3 to 3.2g/m3 and purity of gold between 92.5% to 94%. Having received this information I hired some local labor force to sample part of the lease area we now have. The results in some of the pits dug averaged between 2.2g/m3 to 3.7g/m3 with purity same as results obtained by the geologist from the Geological Survey Department. This license covers an area of about 50.83 acres.

This license is located along the Mandiri River. This river has it’s catchment South-west of the Lake Sonfon. It has been known from earlier work by the Government Geological Survey that it contains gold through out its entire course. Grades of 3.5g/m3 and above are not uncommon at a purity averaging about 97.5%. Because of stringent monitoring by a joint force of government officials and local administration has brought illicit mining of this mineral under control and allows for systematic exploitation of the gold by licensed holders. This license covers an area of about 50.43 acres. It is good to mention here that nuggets have been encountered several times during prospecting by government officials and individuals.

The area under consideration is located within the Sula Mountains greenstone belt which is historically well known for the production of gold in Sierra Leone. This greenstone belt is akin to other greenstone belts around the world such as in southern Africa, Western Australia, and Canada. The Lake Sonfon area just to the south and south west of the Sende Prospect has been explored for its gold potential.
Alluvial exploitation of deposits by artisanal miners in the surrounding is quite wide spread. Although the primary source of gold in this area is not clearly mapped out, the anomaly recorded in reconnaissance and the artisanal mining activities in the area suggest a potential for further exploration. The geology as already described supports this theory.
Abdul K. Mansaray

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