Gayhurst/Dorset Molybdenum Deposit (Copperstream Frontenac-Zone Sud), Lac-Drolet, Le Granit RCM, Estrie, Québec, Canadai

Regional Level Types
Gayhurst/Dorset Molybdenum Deposit (Copperstream Frontenac-Zone Sud)	Deposit
Lac-Drolet	Municipality
Le Granit RCM	Regional County Municipality
Estrie	Administrative Region
Québec	Province
Canada	Country

Gayhurst/ Dorset Deposit - Molybdenum
Also know as Copperstream Frontenac-Zone Sud.

History (from Globex info posted online)
The history of this property dates back to the years 1910-1920 when many trenches were dug on lots 18 and 19 of range IX, Gayhurst Township, in a unsuccessful attempts to find gold. Around 1938, a lumber jack found pieces of rock rich in molybdenite in the rubble from the trenches. Accompanied by a prospector, he later worked the ground on lot 18. In 1941, the mining rights were transferred to Messrs. Dostie and Doyon who, in turn, optioned it to Frontenac Quarries Limited. This company shipped 40 tons of molybdenum bearing rock from lot 18 to Quyon-Molybdenite Ltd., who recovered 155 pounds of molybdenite. In 1943, lots 16 to 23 of range IX were optioned to MacMillan Prospecting Syndicate. In 1956, these lots became the property of Frontenac Mining Corporation. During the same year, a ground magnetometer survey was completed by T.H. Koulomzine counting on the magnetic properties of the pyrrhotite to outline the mineralized zones. As a follow-up to this work, 21 drill holes were completed with a total footage of 17,171 feet. In January 1961, a 1096-foot adit was driven on the south side of Mount Saint-Sebastien, at an elevation of 2148 feet above sea level. This was followed by 1038 feet of drifting in a northerly direction, a 248-foot cross-cut and another drift 184 feet long, parallel to the first drift. The total length of underground working is 2576 feet.
In 1962, the name of the company was changed to Copperstream-Frontenac Mines Ltd., and the property was optioned to Molybdenum Corporation of America. Between July 1962 and December 31st, 1963, this company sampled the underground workings and drilled 30 horizontal holes for a total footage of 3000 feet.
In 1963, Molybdenite Corp. of America did a non NI 43-101 resource calculation which reported 2,000,000 tonnes grading 0.50% MoS2.

At the beginning of 1964, Copperstream-Frontenac Mines Ltd. did underground drilling. At the end of the same year Rio Tinto Canadian Exploration Ltd. optioned the property and drilled 17 holes in the South Zone and 3 in the North Zone. In addition, the company bulk sampled 210 feet of the underground workings.

After Rio Tinto=s work, Molybdenite Corp. of Canada (a name change from America ?) recalculated a resource of 640,000 tonnes grading 0.32% MoS2, a total similar to a calculation done by Rio Tinto (582,900 tonnes grading 0.54% MoS2).

Between 2006 and 2007, Globex undertook a small drill program and completed an I.P. Survey.

This deposit of molybdenite in a Devonian hornfels (mauve in the geological map from Système d'information géominière du Québec, see uploaded photo). The Hornfels was formed during Devonian intrusions of the Sebastian pluton, which was a Devonian biotitic grano-diorite. (Red and pink in map) intruding through a sedimentary formation. This formation is called the member of Milan 1, a Silurian to Devonian feldspathic shall or sandstone/siltstone with local layers of dolomite, mudstone and conglomerates. The Milan 1 sedimentary rock is part of the lower Devonian Compton formation which is the upper part of the St Francis Group. These sediments seem to have been laid down in shallow waters off of the ancient Laurentia coastline resembling a delta deposits.

Type of mineralisation: The mineralisation associated with veins and felsic dykes intersecting sedimentary rocks and connected to Devonian granite intrusions . Genesis, In the Upper Devonian , a large granitic stock settles in the heart of Lower Devonian Sediments . Fractures, cracks and microcracks that affect the sedimentary rocks and even granite are filled with mineralized hydrothermal solutions molybdenum from the terminal phase of the intrusive activity. (This information was translated from Système d'information géominière du Québec).

The following minerals were noted in the same report (Système d'information géominière du Québec): Quartz, Feldspath, Molybdenite, Chalcopyrite, Pyrrhotite, and Pyrite.

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