The drilling programme was completed on time and under budget by African Drilling. The MSA Group of Johannesburg, South Africa, will now conduct a Maiden NI43-101 Resource Estimate, expected to be completed by the end of the third Quarter. MSA have also been contracted to conduct a Preliminary Economic Assessment (PEA) scheduled for completion during the fourth Quarter, 2013. Both drill rigs are currently undergoing maintenance in preparation for a metallurgical and infill drilling programme required to convert identified mineral resources into an indicated category. The required drill spacing will be determined during the resource estimation.
Tin mineralisation at Gecomines has been confirmed over 275m from drilling and is open at depths below 200m. The host rock is generally a chloritic, garnetiferous amphibolite unit within felsic mica schists shown in section in Figures 2 and 3. Occasionally cassiterite bands are developed in the footwall schists in close proximity to the amphibolites where chlorite alteration is less intense. The amphibolite unit is consistently 20-25m thick although in some drill holes the unit and corresponding tin mineralisation might be less due to faulting or quartz veining.
Tin Deportment and Metallurgical Studies
Tin deportment and metallurgical studies were carried out on a 65kg sample of mineralised amphibolite from Bisie. Results of the studies were highly positive with the predominant tin mineral being cassiterite hosted in chlorite schist. The tin is deported evenly throughout the various feed size fractions and no significant upgrading is achieved by screening. The average cassiterite mineralization is relatively coarse at 0.2-0.3 mm. Liberation is partially achieved by crushing and subsequent gravity concentration which would result in a 50 % yield. Rod milling and flotation of the gravity tails would increase the overall yield to 85 %.
Copper is present at 0.2 % as chalcopyrite and needs to be removed from the final concentrate by flotation. Copper recovery would result in less than 3 % contribution to revenue.
Both sulphide and magnetics removal on the concentrate has been allowed for in the process design and no penalties are expected at this stage.
The Bisie project is located in the Walikale district of North Kivu Province DRC and is held by Alphamin's 100% owned Mining and Processing Congo sprl (MPC). MPC holds a total of five tenements covering an area of 1,470sqkm with significant tin, gold and base metal potential. The key prospects within the Bisie Project are the Bisie Tin Prospect mined previously by artisanal means and the Umate gold workings exploited historically by the Belgians and currently mined extensively by artisanal miners.
The Bisie Prospect was the DRC's largest producer of tin ore for a number of years and accounted for up to 75% of the DRC's tin output.
Alphamin lifted force majeure on PR 5266 which hosts the Bisie Prospect in February 2012 and commenced diamond drilling during the second half of 2012 at two main target areas, Gecomines and Golgotha, mined extensively from surface by artisanal miners. Significant high grade tin mineralisation was reported from drilling at both target areas down to depths exceeding 200m. The tin mineralisation is also closely associated with copper and light rare earth (cerium and lanthanum) mineralisation as well as massive and disseminated lead and zinc sulphides and significant amounts of silver. Geochemical soil sampling has highlighted anomalous lead and zinc in soils for a further 3km to the south of the Golgotha workings. Drilling has confirmed a strong association of copper, lead, zinc and tin mineralisation at depth below the soil anomaly which supports the potential for new tin discovery from drilling to the south of Golgotha.
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