Dart Mining NL (ASX: DTM) has announced the first 146 metres of drill results from DUNDD008 extension - the first deep hole at Unicorn to further investigate the long term potential of additional stacked high grade zones at depth similar to the Henderson primary Molybdenum mine in Colorado (USA).
The initial results are very encouraging with 18 metres @ 0.1% MoEq1 being intersected below 476m and a very high grade zone of 4 metres @ 0.22% MoEq1 also being intersected higher in the hole.
The initial assay results are from drilling completed prior to the Christmas shutdown and suggest good potential to define further high grade resources below the current resource base at 400mRL which could substantially increase mine life.
DUNDD008 was the first hole (completed June 2011) to intersect the M3 high grade Molybdenum zone and ended in mineralisation after intersecting approximately 40 metres @ 0.09% MoEq1 from 348m to the end of hole at 387.9 metres.
This M3 zone intersection has now been significantly extended to 92m @ 0.07% MoEq1 containing internal high grade zones of 18m @ 0.12% MoEq1 and 4m @ 0.22% MoEq1.
A new, previously undefined high grade stacked horizon “M4” (not within the current resource) is interpreted below 476 metres with the available assay results from the first assay batch showing an open intersection of 18m @ 0.1% MoEq1 including a higher grade zone of 12m @ 0.12% MoEq1.
Assay data is currently only available to 494m; with the drill core below this showing areas of strong Mo mineralisation within stockwork veins down to 612m.
A previous drill hole, DUNDD005 completed in August 2010 and some 100 metres to the north east intersected a high grade zone at a similar depth to the newly defined M4 zone intersected in DUNDD008, it appears that the two zones may be related in the form of a sub-horizontal layer draped over a porphyry pulse.
This will need to be further tested by subsequent drilling. DUNDD008 has provided significant encouragement that additional high grade mineralisation exists below the current resource base and that with further deep drilling; a potential long term underground resource could be defined.
DUNDD008 is interpreted to have intersected the northern edge of the porphyry complex at 613m, indicating the system plunges to the south. This needs to be thoroughly drill tested prior to testing the continuity of the ore body to 1200 metres.
A decision has been made to commence the prefeasibility metallurgical and geotechnical drilling whilst Dart Mining awaits the analytical test work down to ~659 metres and completes the geological logging and interpretation before recommencing deep drilling.
This change in program will allow results from the metallurgical test work to be available within the time necessary to complete the prefeasibility plant and mine design by Q3 2013.