The Bisha VMS (Volcanogenic Massive Sulphide) District remains under-explored and has vast untapped potential. BMSC has exploration rights on the Bisha and Harena Mining Licenses and the Mogoraib River Exploration License. BMSC continues aggressive exploration to expand existing and find new deposits that have the potential to extend mine life for the Bisha mill.
Exploration targets are presented on figure to the right. Overviews follow of the known mineralization (not in mineral reserve). Bisha plans to target test Tekawuda and Asheli in 2015 as well as work on Harena and the Bisha Main deposit as described below.
Harena VMS (Volcanogenic Massive Sulphide) is situated on the Harena Mining License. Harena is 10 km south of the Bisha Main deposit. Harena was discovered in 2005 following the drilling of a gossan zone associated with felsic volcanic rocks. Harena has a small open pit reserve (see Operations for details) which was mined for oxide gold-silver ore in 2012/2013.
In 2014, exploration drilling was renewed at Harena to explain the large alteration signature of the deposit. The drilling was highly successful and the results are summarized in a news release from December 2014. The resulting increase to Harena resources was announced February 3, 2015. Indicated resources doubled in size to 3.2 million tonnes grading 0.8% copper and 3.8% zinc while inferred resources grew eighteen fold to 6.4 million tonnes with grades of 1.1% copper and 3.7% zinc. The deposit remains open in several directions.
More work is planned in 2015:
- Conduct infill and step-out drilling of 2014 work to grow and increase confidence in resources
- Commence scoping of underground mining
Deposit Configuration - Harena
Bisha Main is makes up over 96% of Bisha reserves. More information is available from Operations page.
The Bisha Main deposit remains open in several directions. In the north end of the current open pit constrained resource the deposit is open, bottoming in high grade primary resource. On strike, the deposit is prospective for both primary and supergene copper mineralization as the deposit trends under a hill next to the pit that has a corresponding geophysical anomaly.
The program of work budgeted for 2015 includes:
- Step-out holes at depth under Bisha Main for primary mineralization extension
- Geophysical target under Guardian Hill for supergene/primary mineralization
- Other geophysical anomaly(s) on Bisha mining License
- Commence scoping of underground mining for Bisha primary at depth
Deposit Configuration - Bisha
The Northwest Zone VMS lies within the Bisha mining license. The Northwest Zone is 2 km from the Bisha Main deposit. Bisha views the Northwest Zone as a potential source of supplemental feed for the processing plant at Bisha. The feed would provide additional cash flow as an extension to mine life without significant capital expense.
Geological mapping of the Bisha area in 2002 identified altered felsic volcanic rocks to the northwest of the (future) Bisha Mine with a coincident strong airborne EM response. In the fall of 2003, diamond drilling intersected potentially economic widths of copper, gold and silver massive and stringer sulphide mineralization. Follow up drilling in 2004 - 2006 and 2012 - 2013 identified copper and zinc VMS mineralization over a strike length of 800m that remains open to the northeast, southwest and at depth.
No further work is planned in 2015 but the favorable horizon north and south remains highly prospective.
Resources - NW Zone
Hambok VMS is a satellite deposit located 16 km southwest of the Bisha mill on the Mogoraib River Exploration License. Bisha views the Hambok deposit as a potential source of supplemental feed for the processing plant at Bisha. The feed would provide additional cash flow as an extension to mine life without significant capital expenses.
The Hambok massive sulphide body is a steeply east dipping, lenticular body. The massive sulphide body extends for over 1,000 m along strike, approximately 350 m down dip and is up to 75 m thick in the center of the lens. The ore body remains open along strike to north and south and down dip at depth.
No further work is planned in 2015 but the Hambok region remains highly prospective.
Resources - Hambok