THE MANSO AMENFI PERMIT - GHANA
Joint Venture Agreement and Location
The Company entered into a joint venture agreement with Asasemu Mining, a Ghanaian company, to develop the Manso Amenfi Prospecting License. Through the agreement GoldStone has the right to earn up to 85% interest in the permit. The Manso Amenfi License is situated in the Wasa Amenfi West District of the Western Region in Ghana, approximately 30 km from the town of Tarkwa and approximately 250 km west of the capital Accra (Figure 1). The permit is approximately 83 square kilometres in extent.
Regional Prospectivity
The Manso Amenfi License is prospective because it lies along strike of a zone of intense artisanal gold mining and the Ayanfuri gold deposit, where Perseus Mining Limited defined a gold resource of 5.3 Moz (Figure 2). The intersection of the Salman structure, which controlled the formation of Adamus Resources Ltd's Salman gold deposit (2.1 Moz), and the Ayanfuri structure abuts the eastern boundary of the License and will be a priority exploration target. Other exploration targets include the margins of two granitic intrusions which straddle the northern and southern concession boundaries. Similar intrusions are known to have controlled the formation of gold mineralisation elsewhere in the Ashantigold belt.
GoldStone’s Exploration
A soil sampling programme covering the central and northern parts of the permit area was completed during April 2011. Samples were collected every 100 metres along north-west trending lines 400 metres apart (Figure 3). The results clearly demonstrate the presence of multiple robust and elongated gold in soil anomalies. The strikes of the anomalies appear to be parallel to gold-fertile Salman and Ayanfuri structures. The programme also resulted in the discovery of a circular gold in soil anomaly in the south-eastern corner of the Manso Amenfi permit area. The western part of this anomaly appears to be within Golden Star’s Pampe Permit and is within three kilometres of the Pampe open pit gold mine. The sampling of the south-western part of the permit area is on-going. Follow-up work may include airborne geophysics and multi-element geochemistry in order to rank the discovered anomalies for follow-up soil sampling and trenching.
During the field programme our geologists also located various artisanal gold mining sites in the permit area. These seem to be exploiting mainly alluvial gold deposits. It was, however, noted that the catchment of the stream that hosts the most prominent alluvial mine site, in the south-western portion of the permit, is completely within the Manso Amenfi permit area. This strongly suggests that the hard-rock gold source of this alluvial deposits also lies within the Manso Amenfi permit area.
Exploration within Trucking Distance of Existing Gold Plant
The license area is within trucking distance (25 km) of Golden Star Resources' ("GSR") Bogoso processing plant. The viability of ore trucking in the area has been demonstrated by GSR who truck ore from their Pampe gold mine, less than five kilometres from the Manso Amenfi License, to their Bogoso plant. The proximity of the Manso Amenfi permit to the processing plant increases the chances of any discovered gold deposit being economically viable. Future exploration of the concession will therefore be guided by the principles of "brown fields exploration"; i.e. directed not only to discover large, stand alone, gold deposits but also to define smaller gold resources that could serve as satellite feeders to the Bogoso plant. This strategy will significantly reduce the discovery risk.
Figure 1: The Manso Amenfi permit is approximately 110 km south-west of the Homase permit and along strike of the Salman (2.1 Moz) and Ayanfuri (5.3 Moz) gold deposits. The rocks in the permit area belong to the volcano-sedimentary sequence of the lower Birimian.
Figure 2: Regional prospectivity of the Manso Amenfi License. The area of interest contains several historical gold in soil anomalies and is close to the intersection of two major, fertile structures. The margins of two granite intrusions form additional exploration targets. The permit is also within trucking distance of Golden Star Resources' Bogoso processing plant.
Figure 3: Results of GoldStone’s soil sampling and artisanal mining activity in the permit area. The results clearly demonstrate the existence of robust, elongated and probably structurally controlled gold anomalies. The catchment of the stream which hosts numerous alluvial gold mining sites in the south-western portion of the permit area lies completely within the permit area and would most likely also contain the hard-rock source of the mined gold.