Dorset JV Project
Location and Description
The Dorset Property is located in Mishibishu Lake Township, 50 km west of Wawa and 300 km east of Thunder Bay. The property area is located on the north shore of Lake Superior, and is accessible via Paint Lake road, an all weather gravel road which links Trans Canada highway 17 to the Eagle River Mine. An ATV– Skidder trail which begins at the 62 km mark along the Paint Lake Road provides direct access to the property.
The property consists of 5 unpatented mining claims occupying 18 claim units covering 992hectares, all within Mishibishu Lake Township. The property is contiguous to Trelawney’s 100% owned Mishi Gold property.
The Dorset Property is currently a joint venture between Trelawney (53%) and MetalCORP (47%) with Trelawney as operator. The property hosts an NI-43-101 compliant indicated resource of 780 000 tonnes at 1.42 g/t Au and an inferred resource of 4 760 000 tonnes at 1.19 g/t Au.
The Dorset Property is located in the Mishibishu Lake Greenstone Belt, an Archean greenstone belt which lies within the Wawa Sub province of the Superior Structural Province. The belt strikes in a rough east west direction, and is approximately 50 km long, and up to 20 km wide. It is broadly concave in shape and the east and west portions strike into Lake Superior.
The Mishibishu Lake greenstone belt is bounded to the north, northeast and northwest by the Pukaskwa granitic batholith, and to the south, by the Floating Heart batholith. At least three major granitic batholiths are located within the belt.
Supracrustal rocks in the belt are similar to other Archean greenstone belts found in northern Ontario. The rocks consist predominately of metavolcanics and metasedimentary rocks, which have been intruded by felsic and mafic dikes and sills. The regional geology has been well described by Bowen, 1985, and others. Approximately 55 % of the Mishibishu Lake belt is underlain by metavolcanic and metasedimentary rocks, with magnesium and iron tholeiitic volcanics covering approximately 20 % of the area. Felsic to intermediate volcanic rocks occupy approximately 15% of the area and clastic metasediments cover approximately 20% of the area. Chemical sediments comprise less than 1%, and occur as sulphide and oxide facies iron formation. These rocks have been intruded by syn-tectonic to post-tectonic intrusive complexes ranging from felsic to intermediate composition.
The supracrustal rocks are Precambrian in age, and have been metamorphosed to upper greenschist facies or lower. Diabase dikes intrude all of the above rocks.
The Dorset deposit is a typical Archean, shear zone hosted deposit. The Dorset Deformation zone strikes in an east west direction dips approximately 45 to 55 degrees to the north and is up to 100 m in width. The deformation zone occurs with a mafic volcanic sequence of rock, in close proximity to a volcanic – sedimentary contact. Gold mineralization within the DDZ occurs predominately in strongly albite and carbonate altered sections, silicified and mineralized with pyrite, arsenopyrite, and pyrrhotite. Gold mineralization appears to be strongly associated with the albite and pyrite arsenopyrite mineralization. The zone appears to have undergone several episodes of strain and quartz flooding.
The Dorset Zone was discovered by prospecting in 1995, when sampling and trenching exposed a gold bearing zone for 1.2km after follow-up of a gold showing found in 1989. The zone is unlike other gold zones of the Mishibishu Greenstone Belt, where the gold is generally hosted within quartz veins. The Dorset Zone is a primary hydrothermal stratiform gold system, with mineralization in an intensely albitized, iron-carbonatized system with finely disseminated 2-3% pyrite and arsenopyrite. The zone is generally 3.0 - 7.0 metres wide with widths up to 22.0 metres.
The Property is located approximately six km north of the Eagle River producing mine, owned by Wesdome Gold Mines Ltd. (~2.0 Mt @ 9.1 g/t Au), within in the Mishibishu Greenstone Belt of northwestern Ontario and is 70 kilometres southeast of the 25 million ounce Hemlo gold camp. The Dorset Property consists of 2,480 acres (992 hectares) and hosts several gold occurrences.
In 2006 and early 2007 Trelawney drilled in excess of 75 holes targeting the Dorset "B" zone and based on this drilling a National Instrument 43-101 resource was released on October 31, 2007. The initial estimate (using a 0.50 g/t Au cutoff) consists of an Indicated Resource of 780,000 tonnes at 1.42 g/t gold and an Inferred Resource of 4.76 million tonnes at 1.19 g/t Au (Cavey and Giroux, 2007) .
In 2008 the Property was further advanced with approximately 3,760 m2 of mechanical stripping on the "B" zone. Results from grab and channel sampling in the stripped area lead to Trelawney commencing a diamond drill program with eight holes completed in late 2008. On February 23, 2009 Trelawney released results from all eight holes, examples of which include 7.52 g/t Au over a core length of 2.5 metres in hole DB-08-02 and 2.78 g/t Au over a core length of 3.3 metres in hole DB-08-06.
In May 2009 Trelawney completed standard preliminary laboratory bottle roll cyanidation, flotation and an acid base accounting ("ABA") test on one small sample (approx. seven kilograms) collected from surface mineralization from "B" zone. The test indicated the sample is non-acid generating but it is refractory to cyanidation with approximately 20% gold recovery. Bottle roll leach and "ABA" testing was completed by Process Research Associates, Richmond, B.C. and flotation testing was conducted by metallurgical consultant, Westcoast Mineral Testing Inc., Vancouver. Due to the small sample size and with only one sample analyzed, Trelawney reported that the gold recovery may not be representative of the entire Dorset "B" zone; metallurgical testing on the Dorset Main Zone in the Fall of 2009 returned similar metallurgical test results with poor gold recoveries.
To review the entire 43-101 Technical Report on the Dorset property please click here.