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AMN - GHANA: Wassa significantly advanced

Golden Star has updated its activities at Wassa gold mine in Ghana. The Wassa Underground has advanced significantly since development began in July 2015.

It has gone from a single ore body (the B Shoot) to adding the F Shoot which Golden Star believes to be a parallel zone to the main mining stopes along the B Shoot structure.

The underground economic potential of the F Shoot was first recognised in 2014 when stope optimisations were conducted for the company's Preliminary Economic Assessment of the Wassa Underground.

The initial resource was small and only consisted of a few stopes which were defined by a handful of holes; it was therefore decided to further test this target in early 2015 utilising surface drill rigs.  The results of this drilling were used to update the Wassa Underground resource models used for the Feasibility Study on the Wassa Underground completed in 2015.

The company plans to publish its 2015 year-end mineral reserves and resources statements which will include additions for the F Shoot target that were delineated during 2015 drilling. The recent drilling programs have successfully extended the F Shoot target north of the current reserve and the company plans to assess the full potential of the F Shoot, which remains open down plunge to the south.  

Highlights of the drill program 

-          FSDD010 – 22.0 meters (grading 3.5 grams per tonne gold 

-          FSSDD011 – 8.4 metres grading 5.6 grams/tonne

The main and ventilation declines have reached a position where access to the F Shoot mineralisation is being developed. The twin declines will continue down plunge to access the B Shoot stope areas.

The declines have advanced approximately 1060 metres in total since development start-up in July 2015.

Golden Star president and CEO Sam Coetzer says: "These drill results, testing the extension of the F Shoot mineralisation north of the planned mining stopes, are very encouraging. We expect future F Shoot drilling programs to continue to add ounces to the Wassa Underground resources and reserves. These drilling results indicate grades and thicknesses that could be mined underground and the location of these zones allows quick access to this area, potentially adding ounces to our near term production. " 

The Wassa Underground development has advanced significantly and is on schedule to gain access to the first F Shoot stopes in the second quarter of 2016.  During the development of the twin declines, the northern projection of the F Shoot structure was intersected along 24 meters of development in both drives. The presence of this zone in the underground development and intersections of higher grade mineralisation in existing drill holes supported further drilling to test the continuity and geometry of the northern extension of the F Shoot structure.

Four holes were collared from the bottom of the Starter Pit, targeting the projection of the F Shoot, with all four holes intersecting the zone. Significant intersections included FSDD010, which intersected an estimated true width of mineralisation of 22 metres grading 3.5 grams/tonne and was inclusive of a higher grade zone of 3.3 metres which yielded a grade of 9.2 grams/tonne. This particular hole was drilled to confirm the grades intersected in STDD018, 20.6 metres grading 2.7 grams/tonne which is located approximately 10 metres to the south of FSDD010. The F Shoot is characterized by up to three parallel zones, FSDD010 intersected what has been interpreted to be the middle zone where FSDD011 has intersected the upper and lower zones.

The upper zone in FSDD011, 8.4 metres grading 5.6 g grams/tonne, including 3.2 meters at 12.7 grams/tonne, was intersected 15 meters up dip from hole STDD012, which generated an intercept of 4.6 meters at a grade of 3.0 grams/tonne. The lower zone in FSDD011, 6.5 metres grading 3.8 grams/tonne, extended the gold mineralisation approximately 30 meters down dip of STDD019 which intersected 6.1 metres at a grade of 5.8 grams/tonne.  The results from this phase of drilling have shown that grades and thicknesses amenable to underground mining exist north of the current F Shoot designed mining stopes, and therefore additional drilling is being planned from both surface and underground to better delineate the higher grade portions of the structure. The drilling program is expected to begin in the first quarter of 2016.  

www.gsr.com

News courtesy of International Mining