The Cassiar Moly occurrence is located roughly 5 kilometres south of the former mining community of Cassiar, approximately 7 kilometres west of the Cassiar Highway.
The Cassiar Moly deposit occurs in the Late Cretaceous Troutline Creek quartz monzonite stock, at the eastern margin of the Early Cretaceous Cassiar Batholith. Intrusive phases include a pink megacrystic porphyry, a coarse-grained porphyry, a grey porphyry and a finer-grained equigranular leucocratic quartz monzonite. All textural variants have gradational contacts. Alaskite, aplite and quartz-feldspar porphyry dikes and segregations occur throughout.
Molybdenite occurs as small rosettes and flakes in the fine-grained intrusions and in fractures and joints with pyrite within quartz-feldspar porphyries and adjoining megacrystic porphyries. The main mineralized zone trends north to northeast, following the main joint and fault trend. Locally, quartz-rich pegmatite pods up to 12 metres in size contain coarse molybdenite crystals or, rarely, quartz-sericite-rutile-molybdenite greisen. Chalcopyrite occurs in minor amounts along fractures and as disseminations. Powellite has been identified in sericitic rocks. Stockworks and breccia zones are generally absent.
Mineralization is scattered over a 460- by 460-metre area with local high-grades over narrow widths. The overall grade is low (0.026 per cent molybdenum) across 100 metres (Energy, Mines and Resources Mineral Bulletin MR 223, 1989).
Other zones of molybdenite mineralization are reported on a north-trending ridge, approximately 700 metres north of the main zone.
Work History
The area was first staked by J. Hope and a partner. In 1966, the Rusty Group property, now termed Cassiar Moly, of Value Line Minerals Ltd. was examined by H.W. Agnew, who recommended that the property be prospected, geologically mapped and soil sampled; this program was completed by Associated Geological Services Ltd. In 1967, Dolmage-Campbell & Associates Ltd. examined the main showing of the property and a subsequent report by D.D. Campbell recommended a winter underground exploration program to best explore the main mineral showing. Following this recommendation an exploration adit was begun on the property in November 1967. The heading, planned to be a 914-metre exploration crosscut, was driven a length of 137 metres before the operation was shut down in February 1968 due to lack of water. Later in 1968, the adit was continued to 785 metres and a new access road was constructed from the Stewart–Cassiar Highway. The following year, a 305-metre-long drift was driven north from the adit and passed below the southern half of the surface occurrence.
In 1978, J. McClintock, staff geologist for Rio Tinto Canadian Exploration Limited, conducted a property examination and at that time and again, as part of follow-up work, resampled parts of the Cassiar Moly adit. In 1979, Cassiar Asbestos conducted a program of prospecting, geological mapping and rock sampling on the area as the Angel 2 and Sun claims. This work identified mineralized zones, including powellite (tungsten) mineralization, not previously mapped, especially along the eastern and western cirques of the property. A sample (22250) hosting powellite and molybdenite, taken approximately 300 metres southwest of the main occurrence area, assayed 14.50 per cent molybdenite and 0.49 per cent tungsten (Assessment Report 8009).
In 1980, Cassiar Resources Ltd. completed three diamond drill holes, totalling 1369.0 metres, on the Cassiar Molly property.
In 2006, prospecting was conducted by G. Diakow and J. Hope; outcrop was mapped and numerous trenches from earlier explorers were located and sampled. In 2008, Velocity Minerals Ltd. undertook a program of work to reopen the adit that was driven in 1969, and also improved the road to the adit portal and retimbered the portal in preparation to re-enter the tunnel and remove an ice plug, which blocked the adit for approximately 200 metres.
In 2009, Velocity removed ice and re-established sufficient venting to generally reopen the adit so that it could be surveyed, resampled and geologically mapped. In 2010, Velocity Minerals Ltd. conducted a drill program consisting of three NQ-core drillholes from one setup for a total of 1396.29 metres. Drillhole CM 1 09 was lost during winter while mothballing of the drill rig on the mountain side. Drillhole CM 2 10 was started from the same position as CM 1 09, approximately 30 centimetres east of its collar. CM 2 10 was located so that the hole would undercut the surface mineralization exposed on the steep slope and what had been observed in the historical adit driven by Value Line during the winter of 1968 and summer 1969. The hole was designed to test updip continuity of a mineralized zone in the crosscut of the underground workings. Assay results for CM 2 10 yielded large intervals of low-grade molybdenum. These include a 64.01-metre interval (from 78.33 to 142.34 metres) of 0.02 per cent molybdenum, a 42.67-metre interval (from 151.99 to 194.16 metres) of 0.016 per cent molybdenum, and a 30.48-metre interval (from 285.6 to 316.08 metres) of 0.016 per cent molybdenum. The dominant rock types in this hole are a quartz-feldspar porphyry and a quartz monzonite (Assessment Report 33394).
