"""Grey River Tungsten
Location, Access & Infrastructure: The property is located adjacent to the fishing village of Grey River (population of ~ 350 people) on the south coast of Newfoundland. Grey River is serviced daily by coastal boat from Burgeo, a coastal port about 40 km to the west. Burgeo is linked by a highway to the Trans Canada Highway and the airport town of Stephenville approximately 125 km to the north. The claims are accessed by foot and helicopter while the Main Zone adit is within 150 metres by gravel trail from Grey River village. A local diesel supplies electricity to Grey River. A large government owned wharf exists in Grey River.
A 6,300 foot long (1,920 metre) adit has been driven into the Main Vein from near the village of Grey River at approximately 40 metres above sea level. Docking and wharf facilities existed at the Asarco adit but the present conditions are not known.
Property & Ownership: The property consists of nine mineral claims (1,750 hectares) that were map staked on August 24, 2000 and July 10, 2001. The claims, were acquired from South Coast Ventures by Playfair Mining (100%). The property is covered on claim map sheet NTS 11P/11.
Exploration History: Tungsten mineralization was first noted near Grey River around 1956. Subsequent exploration by Asarco during 1957 to 1970 included surface geological mapping, trenching and diamond drilling on five of the better veins, driving a 6,300 foot long exploration adit into and along the Main (#10) vein, driving 20 short raises into the vein and collecting a 275 ton bulk sample for a number of metallurgical tests by Asarco and CanMet. Asarco had destined the project for production around 1970 but the drop in tungsten prices shelved the project. The property changed hands several times but no further work was done from 1970 to present day. The claims expired in June 2000 and were map staked by South Coast Ventures when the Newfoundland government released the ground for staking.
Geology: The immediate area is underlain by Ordovician-Silurian age metasedimentary amphibolites and quartz-mica schists and gneisses that predominate to the north. Bedding and foliation-banding strike E-W and dip steeply north. Extensive granitic rocks predominate north of the metasedimentary units. Pegmatites cut all rocks and can form considerable amounts locally. Three prominent fault sets occur; an E-W set is the strongest and brings metasedimentary rocks into contact (usually mylonitic) with the granitic rocks. A younger north to NE trending fault set is commonly occupied by quartz veins hosting the tungsten mineralization.
Mineralization: The Grey River tungsten veins are typical fluorite-rich wolframite-quartz greisen vein deposits. Most of the tungsten mineralization is wolframite with a number of small scheelite occurrences known. GSC Economic Geology Report 32 (Geology of Canadian Tungsten Occurrences, R. Mulligan, 1984) lists the Grey River deposits as "one of the largest typical wolframite deposits in Canada" and states "in view of the geological environment and the presence of beryllium, molybdenum, fluorite and base metal deposits, it would be remarkable if there were not many more tungsten occurrences' (on the property).
The wolframite veins occur mainly in the metamorphic rocks but also in the granitic rocks to the north. Over 300 veins and lenses have been mapped on surface although to date only two or three appear significant enough to have been partially evaluated by Asarco. The Main (#10) Vein is from 0.9 to over 4.3 m wide and averages ~1.2 m wide (based on underground mapping) and has been traced for over 1,600 m long with the #10 oreshoot over 775m long. Over 240 m vertical thickness is defined above the adit. The vein increases in width with depth and appears to also increase in grade with depth. Tungsten grades substantially increase with face sampling and bulk sampling compared to drill hole grades; this is likely a result of poor drill core recoveries but is also due to a significant 'nugget effect'.
Resources* & Potential: Asarco calculated a proven & probable "reserve" in one vein (Main or #10 Vein) based on surface trenching and drilling but mostly based on underground drifting, raising and bulk sampling. These figures are strictly above the adit (40 metres above sea level) to surface. Asarco's "mineable, diluted reserves",prior to and not 43-101 compliant, are 520,000 tons grading 0.97% WO3. The calculated grade of 1.09% WO3 very closely matched the 275 ton bulk sample derived from the raises which averaged 0.97% WO3. The actual in place non-diluted grade of the vein in the raises would be approximately 1.4% WO3.
A significant potential for additional tungsten reserves exist on the property. Additional targets include the following:
Low-grade sections of the vein can carry zones averaging 0.28% WO3 and better. Asarco largely ignored these grades in the past.
Dozens of additional tungsten-greisen veins are known over the property but have yet to be explored.
Low-grade areas of the adjacent wall rock which where tested by only a few short percussion test holes returned WO3 values. Essentially Asarco never sampled or assayed any rock outside of the quartz veins and only then if visible wolframite-pyrite was visible. A potential for bulk tonnage low grade deposits exists.
Little work has been done with respect to metal zoning, however a Cu, Zn-Pb, Mo, Sb and Sn zonation appears to exist in within a 3 to 5 km radius around the tungsten deposits.
Limy rocks adjacent to the north granite and the E-W fault hold an excellent potential for skarn WO3 mineralization; this has never been tested despite the adjacent occurrences of narrow tungsten greisen veins.
In 1997 a significant but low grade porphyry Cu-Mo-Au deposit was partially outlined about 500 to 1,000 metres north of the property.
From 1995 to 1998 local prospectors have obtained high-grade gold values (to several ounces) from veins and alteration zones within several km of the property.
Conclusions:
Past work on the Grey River Tungsten Project has shown there is significant and widespread tungsten mineralization with an important " mineable reserve", not 43-101 compliant, of good grade wolframite. The immediate proximity of the deposit to the village of Grey River and the existence of a 1,920 metre long adit located 40 metres above sea level bode well for this project.
Asarco explored the property during the late 1950's and 1960's. Despite finding dozens of tungsten greisen veins only two were seriously explored with excellent results. A very significant potential still exists within the Grey River Project for locating new WO3 reserves both in high-grade veins and lower grade bulk tonnage deposits.
* Estimates of tungsten resources are historical in nature, predate and are noncompliant with NI 43-101. Playfair is not treating the historical estimate as current mineral resources or reserves. Playfair has not undertaken any independent investigation of the resource estimates nor has independently analyzed the results of the previous exploration work in order to verify the resources, and therefore the historical estimates should not be relied upon. However, Playfair believes that these historical estimates provide a conceptual indication of the potential of the occurrences and are relevant to ongoing exploration. """ |
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