The J & J prospect is situated south of the Nahatlatch River, approximately five kilometres up from its confluence with the Fraser River and nineteen kilometres north-northwest of Boston Bar. The prospect is owned by Pacific Talc Ltd. and property evaluation managed by A. Ismay Associates Inc.
Talc occurrences in the lower Nahatlatch Valley were recognized since before 1900. The Gisby claims located just south of the confluence of the Nahatlatch River with the Fraser River, were staked as a gold prospect and covered a number of talc and silica showings. Small amounts of silica and talc were mined from the group on the 1920s. The J & J claims were staked in 1970 and 1971 to cover a talc showing exposed for about 40 metres along the Nahatlatch River road. Preliminary work involved surface trenching and sampling to investigate the extent of the talc body. Samples were shipped to Lakefield Research of Canada Ltd. and to Department of Energy, Mines and Resources of Canada, Mineral Processing Division for analyses. During the mid-1970s, a series of bulk samples were taken by Pacific Talc Ltd. and at least one sold to a Inuit art co-operative as carving stone. In late 1977, the claims were optioned to Mountain Minerals Co. Ltd., who conducted an extensive surface and subsurface evaluation of the property. Seven diamond-drill holes totalling 470 metres were completed along strike in 1978 and 1979. In late 1979, a 5.44-tonne bulk sample was taken and sent to a processing facility in Lethbridge, Alberta. The option was dropped in the early 1980s. In 1984, a compilation report, which included reserve estimations, was made. In 1987, S.A.S. Croft of Nevin Sadlier-Brown Goodbrand Ltd. conducted an engineering evaluation of the deposit and recommended further development. In 1988, several bulk samples were shipped to Ontario Research Foundation where flotation testing was completed. It was concluded the talc was marketable. In 1989, Bacon, Donaldson and Associates continued metallurgical test work to refine the flotation process. A test pit program was completed in 1989 under the direction of Steffen, Robertson and Kirsten to confirm or refine the assumed extent of the talc body over the southeastern half of the deposit. A technical and economic feasibility study was initiated by Pacific Talc Ltd. in 1990. In 1991, 13 drillholes totalling 1131.3 metres were completed to increase and define proven reserves.
A narrow, north-northwest trending belt of Permian to Jurassic Bridge River Complex (Group) metasediments occurs along and parallel to the Fraser River. These rocks are cut by many small serpentinized ultramafic intrusions. The Bridge River Complex is in contact with sediments of the Early and Middle Jurassic Ladner and Early and Middle Cretaceous Jackass Mountain groups along faults of the Fraser fault system to the east and west. Further west, metasediments of the Cretaceous Settler Schist, in fault contact with Ladner Group rocks, have been intruded by plutonic rocks of the Late Cretaceous Scuzzy pluton.
Geology in the area of the Pacific Talc occurrence is characterized by northwest striking, subvertically dipping, strongly schistose, chloritic phyllite and graphitic to quartzose phyllite of the Ladner Group.
The J & J talc deposit is a tabular, elongate body of sheared talc-magnesite-chlorite-dolomite rock hosted by medium to dark grey-green phyllite, striking approximately 130 degrees with vertical to steep northeast dips. The talc body appears conformable with the phyllite host. It ranges from 10 to 700 metres wide, averaging 45 metres, in northern exposures, up to 10 metres wide in southern exposures and has a strike length of 600 metres. Drilling indicates the talc body extends to a depth of at least 110 metres. The limits of the body remain open or undefined at depth and to the southeast.
The dark grey-green talc is platy and weathers to a buff to brown colour. It is associated with carbonates (magnesite and some dolomite), chlorite, serpentinite, limonite and magnetite. Up to five per cent pyrite is visible, mainly along fractures as well as disseminated throughout the rock. Thin sections show that the talc forms a fine-grained groundmass within which is enclosed larger (0.5 to 1.0-millimetre) grains or grain aggregates of carbonate (magnesite and dolomite). Locally, particularly near its contact with the phyllite, the talc body becomes increasingly chloritic.
Analytical data indicates that the material from the talc deposit comprises an admixture of talc (60 per cent) and magnesite (30 per cent), with minor amounts of chlorite (3 to 8 per cent), and lesser carbonates (0.5 to 2 per cent). Iron content (reported as Fe2O3) is in the order of 6 per cent. None of the analyses have detected deleterious minerals such as tremolite, actinolite or serpentines (Property File - Prospectus, Pacific Talc Ltd., 1989).
In 1991, a thirteen hole diamond drilling program was carried out in two phases to define the J & J talc deposit.
As part of a test program carried out in 1991, Pacific Talc Ltd. produced talc for use as pigment in the manufacture of paper samples called 'handsheets'. An integrated process pilot test was completed by Pacific Talc Ltd. on June 30, 1992. It consisted of taking a large bulk sample from the deposit, producing a talc concentrate by conventional flotation and then treating the concentrate in Pacific Talc's proprietary process to produce a final product that is hydrophilic and meets the specifications for paper filler pigments. The talc filler produced in the process pilot plant was then used in a subsequent pilot paper machine in the United States. Paper pulp from a British Columbia producer was shipped for these trials. Three grades (uncoated, mechanical pulp based, supercalendered printing and uncoated woodfree (photocopy type)) of paper were produced successfully and samples of each were then tested for mechanical, optical and printing properties. Both the process pilot plant and pilot paper trials have been successful and have demonstrated that talc produced through this method can be used as paper pigment, and also generated the information required for the engineering study (George Cross News Letter No. 205 (October 23), 1992).
Preliminary estimates put deposit reserves at about 8.2 million tonnes grading 60 per cent talc (Northern Miner - March 1, 1993).