The Siou mineralized sector was discovered in the third quarter 2012 and rapidly became an exploration priority. This discovery is more significant than the initial Nyafe and Wona discoveries, which led to the construction of the Mana processing plant.
The initial inferred resource estimate at Siou could enhance the head-grade at the Mana processing plant for years to come. This could provide great synergy with current mining operations and should consequently reduce total cash cost per ounce at Mana should the Siou Deposit advance to production.
Delineation drilling is underway at Siou with the objective to convert as much of the in-pit inferred resources to the proven and probable reserves category in the third quarter of 2013. The Corporation's goal is to begin mining the sector in late 2014 or early 2015. In addition, exploration drilling is underway in order to test the potential of lateral extension and to better establish the continuity of the deeper mineralization.
On a larger scale, our exploration priority remains the Kokoi trend. The Siou Sector mineralization originates from an important contrast of rock competencies between the granodiorite and sediments in the shear zone. Prospectiveness along the 30-kilometer long shear is obviously in the same geological environment, but may also be favorable between massive volcanics and sediments as in the first anomaly found at Kokoi (2.57 g/t Au over 7 meters, Ref. Figure 3)
These inferred resources will be included in the Corporation's 2012 consolidated reserves and resources estimate scheduled for release in March 2013.
A National Instrument 43-101 compliant technical report will be filed on SEDAR within 45 days of this press release.
The estimation database includes 132 reverse-circulation holes (17,600 meters) and 46 diamond-drill holes (9,500 meters). The specific parameters used for the Siou inferred resources estimate include:
-- Minimum of three holes to allow interpolation in block model-- A 15% dilution applied-- A 95% carbon-in-leach mill recovery rate in both oxide and sulfide mineralization (reference SEMAFO's press release dated February 7, 2013)-- Costs include transportation to the Mana processing plant (15 km)-- Other cost parameters used are the same as the resource cost parameters in the Advanced Technical Report, Mana Property (NI 43-101) dated July 11, 2012
Geostatistical analyses generate a capping grade of 40 g/t Au for the Siou, the Nine and the 55 Zones, affecting 2.6% of the 870 composites and removing 9% of the included metal. All other zones are capped at 35 g/t Au.
Michel Crevier, P.Geo MScA, Vice-President Exploration and Mine Geology is SEMAFO's Qualified Person and has reviewed this press release for accuracy and compliance with National Instrument 43-101.
All individual samples represent approximately one-meter in length of core, which was sawn in half. Half of the core is kept on site for reference and its counterpart is sent for preparation and gold assaying to the ALS Mineral Division laboratories in Ouagadougou, Burkina Faso or to SEMAFO's Mana Mine Lab, which uses separate sample preparation equipment exclusive to exploration samples. For reverse-circulation drilling, all individual samples represent approximately one-meter in length of rock chips homogenized and riffle-split to an approximate two-kilogram subsample, which is sent for preparation and gold assaying to the ALS Mineral Division laboratories in Ouagadougou, Burkina Faso or to SEMAFO's Mana Mine Lab. Each sample (reverse-circulation and air core) is fire-assayed for gold content on a 50-gram subsample. In addition to ALS Mineral Division's own QA/QC (Quality Assurance/Quality Control) program and Mana Lab's own QA/QC program, an internal quality control and quality assurance program is in place throughout the sampling program, using blind duplicates, blanks and recognized industry standards.