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File Created: 24-Jul-1985 by BC Geological Survey (BCGS)
Last Edit:  23-Oct-2014 by George Owsiacki (GO)

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NMI 104P4 Au9
BCGS Map 104P012
Status Past Producer NTS Map 104P04E
Latitude 059º 11' 44'' UTM 09 (NAD 83)
Longitude 129º 41' 06'' Northing 6562028
Easting 460869
Commodities Gold, Silver, Zinc, Lead, Copper, Antimony, Bismuth, Cadmium Deposit Types I01 : Au-quartz veins
Tectonic Belt Omineca Terrane Slide Mountain
Capsule Geology

The Cusac mine is approximately 4 kilometres south of the main Erickson mine (104P 029). Previously, mining was done on the Dino and Hot vein systems but the main ore zone is the Eileen vein system. The Eileen vein was discovered in 1985 and production commenced in 1986; to date, the vein has been mined over a strike length of 300 metres and downdip for approximately 30 metres. The Michelle vein, approximately 30 metres from the Eileen, was also discovered in 1985 and has had limited work done on it (A. Boronowski, personal communication, November 1988).

The Cusac veins are hosted by the Devonian-Triassic Sylvester Allochthon. The Sylvester Allochthon is a fault-bounded imbricate assemblage of regionally metamorphosed (greenschist facies) oceanic crust consisting of metavolcanics, metasediments and ultramafics. Potassium-argon dating of sericite from a quartz stringer associated with an auriferous quartz vein hosted by metavolcanics, indicate a Lower Cretaceous age.

In the mine area, the Mississippian to Upper Triassic Slide Mountain Complex assemblage consists of greenstones, argillite, serpentinite, listwanite and quartz veins. Two sets of steeply dipping quartz veins are known, one striking northward, the other east. The veins occupy fault and fracture zones, mainly in footwall greenstones adjacent to a greenstone-argillite contact and vary in width from 0.75 to 3.0 metres. The north striking system has been traced for at least 750 metres.

The mineralization consists of galena, pyrite, sphalerite, chalcopyrite, tetrahedrite and gold. The hostrock adjacent to the quartz veins has been silicified, contain graphitic alteration, and the serpentinites have commonly been altered to listwanite. It has been noted that where quartz veins cut or lie directly beneath a listwanite body the gold values for that portion of the vein increase. Dussell (1986) proposes that "ore solution infiltrated and metasomatized bodies of partially serpentinized peridotite producing a listwanite. Gold precipitation was then triggered by a decrease in sulfur activity when the ore solution reacted with the listwanite parent". Pyrite occurs as coarse grained and fine-grained knots throughout, but increases in abundance towards the wallrock contact. Sphalerite, tetrahedrite and minor galena occur within the pyrite knots and normally indicate better gold grades.

Two new veins, the Heather and Bain veins, have recently been discovered on the property. The Bain vein is a well mineralized, steeply dipping east-west structure. A 39-metre section of the vein assayed in the 51.4 to 68.5 grams per tonne gold range uncut over 1.2 to 1.8 metre widths indicated by surface trenching and drilling (George Cross News Letter No.35, 1990). The Bain vein is 457 metres south of the Eileen vein system.

Past production at Cusac is included as part of the Erickson mine (104P 029).

Current reserves at the East Bain are 21,770 tonnes grading 17.1 grams per tonne gold; unclassified reserves at the Michelle are 22,677 tonnes grading 27.4 grams per tonne gold; current reserves at the Bonanza are 4535 tonnes grading 17.1 grams per tonne gold; current reserves at the West Bain are 31,748 tonnes grading 34.28 grams per tonne gold; unclassified reserves of three surface pits are 9071 tonnes grading 10.2 grams per tonne gold (George Cross News Letter No.90 (May 11), 1994; P. Wojdak, personal communication, 1995).

Cusac Gold Mines Ltd. produced 489 kilograms of gold in 1994 from approximately 31,075 tonnes of ore, milled intermittently at a daily throughput of 275 tonnes. During 1995, Cusac completed a decline to the Michelle high-grade zone and continued to develop the zone, producing about 45 tonnes of development ore per day for blending with the lower grade Bain vein material.

As a result of encouraging drilling results in the Michelle high-grade zone, Cusac is proceeding with completion of the 10 portal, a major underground development project, to improve access to the orebody and, ultimately, to increase production. Cusac will advance the partially constructed adit (1570 metres) approximately 915 metres to the target area, with planned completion in the spring of 1996. Meanwhile, mining, development and exploration will continue through the existing decline. The mill is currently processing high-grade material from both the Michelle high-grade zone and the Catherine vein (104P 113) open pit. The mill has been winterized and is expected to continue operating through most of the winter. Milling resumed in September 1995 and gold production, from intermittent daily throughput of 150 tonnes to the end of October, is approximately 300 kilograms (Information Circular 1996-1, page 8).

In 1995, with Explore B.C. Program support, Cusac Industries Ltd. completed 2802.3 metres of underground diamond drilling in 31 holes on the Michelle vein. This work proved that the Michelle vein is high grade but also complexly faulted. The drilling also discovered a second high grade ore shoot, the Lily vein, subparallel to Michelle. A drill indicated reserve of 10,000 tonnes grading 96.3 grams per tonne gold has been outlined in the Lily vein which has greater downplunge and strike extension potential than Michelle (Explore B.C. Program 95/96 - A143).

The mine, had, to the end of August 1996, produced 489,047 grams gold. Total reserves at Table Mountain (including the Vollaug vein) are 131,120 tonnes grading 12.69 grams per tonne gold (Northern Miner - October 14, 1996). The published reserve in 1997 is 139,635 tonnes grading 10.29 grams per tonne gold (Northern Miner - April 7, 1997).

Underground mining in the Michelle Highgrade zone (including Lily Vein extension) was suspended in June 1997. Mining has taken place over an 800 metre strike. Opencut mining of the Vollaug vein was expected to end in August 1997 and the mill will shut down shortly thereafter.

The company estimates current proven and probable reserves at 72,568 tonnes grading 17.1 grams per tonne gold (T. Schroeter, personal communication, 1997).

In 1998, Cusac mined the Bear vein (104P 029) and produced 28,522 grams of gold from 1800 tonnes.

In 2002, Cusac Gold Mines Ltd. completed a 1022 metre drill program on the eastern part of the Bain vein (Press Release - Cusac Gold Mines Ltd., September 20, 2002). In 2003, Cusac Gold Mines Ltd, completed two diamond-drill holes on the Gap zone totalling 626 metres. The mine has been on care and maintenance status since 1999. In 2002, drilling defined a resource of 22,000 tonnes grading 33.78 grams per tonne gold on the east extension of the Bain vein (Mineral Exploration Review 2003, page 16).

In 2004, exploration drilling (6478 metres in 41 holes) resulted in discovery of a new vein by Cusac Gold Mines Ltd. The Rory vein trends 020 degrees and dips steeply to the west. It was found north of the Jennie and Bear veins in a prospective but relatively unexplored portion of the property. The Rory vein averages 3 metres in true width over a length of 130 metres and dip extent of 45 metres, and is 25 metres above a main haulage drift. The Rory vein contains an indicated mineral resource of 19,958 tonnes at 12.17 grams per tonne and an inferred mineral resource of 1899 tonnes at 11.31 grams per tonne gold (Press Release - Cusac Gold Mines Ltd., November 22, 2004). The Rory and East Bain veins contain a combined total indicated resource of 40,059 tonnes at 16.9 grams per tonne gold ) and a total inferred mineral resource of 3056 tonnes at 33.00 grams per tonne gold (Press Release - Cusac Gold Mines Ltd., November 22, 2004). National Instrument 43-101 compliancy was not reported.

In 2005, Cusac turned its attention to the nearby Taurus II property (104P 016,77).

In 2006, Cusac Gold Mines Ltd. rehabilitated the underground workings and restarted mining operations and mill/facilities rehabilitation in mid-August. The company expects its first gold pour in mid-November; work is on the East Bain and Rory veins. Resources reported by the company are a combined probable mineral reserve of 39,916 tonnes grading 15.24 grams per tonne. Also reported are inferred mineral resources of 3056 tonne grading 29.86 grams per tonne for the East Bain vein alone. The initial focus was on the Rory vein with minor production, but then shifted to the Bain vein where a probable reserve of 25,000 tonnes grading 17 grams per tonne gold has been identified. The company completed considerable underground work, including advancing a decline to 150 metres from the East Bain vein when it intersected high water flow that halted mining on October 1, 2007 (Information Circular 2008-1, page 6).

Winterization of the Table Mountain Gold Mine was successfully completed to ensure a smooth resumption of development and mining activities in the spring of 2008. At that time, management has determined that larger scale pumping equipment and other measures will enable the company to handle the volumes of water encountered in the East Bain Decline earlier this year. A number of small quartz veins were intersected in the East Bain Decline containing visible gold. Assays from these veins confirm the visual observations, with grades of 53.5 grams per tonne gold over 0.2 metre and 48.7 grams per tonne gold over 0.2 metre in two of these quartz stringers. Although the veins are not of minable width, they are a good indicator of pathways for gold-bearing fluids and they may lead to possible new vein systems in the area.

In 2007-08, Hawthorne Gold Corporation and Cusac Gold Mines Ltd. entered into a merger agreement whereby the two companies would continue to operate under the corporate entity of Hawthorne Gold Corporation. Hawthorne became the owner and operator of Cusac’s Table Mountain and Taurus (104P 012) properties and proceeded to form a private subsidiary company, Cassiar Gold Corporation, to retain assets acquired from Cusac. The entirety of this land package became known as the Cassiar Gold property. Table Mountain project areas contain the historic Erickson Gold Mines mine site (104P 029) located adjacent to the southern shores of McDame Lake, historic underground workings at the Main Mine area along Erickson Creek, historical portals used to mine and access the Vollaug vein (104P 019) on top of Table Mountain and east of the Main Mine, and the Cusac and Bain Portals approximately 8 kilometres south of the Main Mine. The Taurus project area is approximately 6 kilometres north of the Main Mine and contain the historic Taurus, Sable, and Plaza portals and underground workings. The intent of the 2008 exploration year was to reassess the overall scope of the Cassiar Gold property. The exploration program comprised field reconnaissance, soil sampling (606 samples), rock and chip sampling (365 samples), airborne magnetic and VLF-EM surveying (6567 kilometres), geophysics ground truthing, and diamond drilling (15 holes totalling 2536.5 metres on the East Bain vein, 104P 070).

Between 2007 and 2010, Hawthorne Gold Corp. consolidated the Cassiar Gold Project by acquiring 46 mineral claims from American Bonanza Gold Corp., 46 mineral claims from Cusac Gold Mines and 124 mineral claims by staking or other mineral claim purchases.

In 2010, Cassiar Gold Corp., a wholly owned subsidiary of China Minerals Mining Corporation, completed a helicopter-borne time domain-EM, magnetic and radiometric survey covering 5090 line kilometres.

On April 5, 2011, Hawthorne was renamed China Minerals Mining Corporation. During 2012, China Minerals Mining Corporation completed drilling campaigns at the Taurus (104P 012, 43 holes) and Table Mountain (10 holes) properties of their Cassiar Gold Project.

EMPR Explore B.C. Program 95/96 - A143
EMPR EXPL 1979-316,317; 1980-514; 1986-C461,C462; 1996-B6; 1997-13; 1998-24; 2003-7; 2004-26
EMPR FIELDWORK *1980, p. 55; 1981, pp. 156-161; 1987, pp. 245-248; 1988, pp. 339-344
EMPR MER 1985, p. 9; 2003, p. 16; 2004, p. 13
EMPR INF CIRC 1989-1, p. 13; 1993-13, p. 14; 1994-1, p. 14; 1994-19, p. 8; 1995-1, p. 8; 1995-9, p. 8; 1996-1, p. 8; 1997-1, p. 10; 1998-1, pp. 9-10; 2000-1, p. 6, 2008-1, p. 6
EMPR MAP 65 (1989)
EMPR MINING 1981-1985
EMPR OF 1992-1; 1994-1; 1996-11
EMPR P 1991-4, pp. 188,189
EMPR PF (Cusac Attains 50 TDP Mining-Milling Gold Ore in British Columbia, Table Mountain Mine, Nov./Dec. 1982; Boronowski, A. (1988): Erickson Gold Camp, Geology and Metallogeny of North-western British Columbia, Smithers Exploration Group - G.A.C. Cordilleran Section, Workshop Oct. 16-19, 1988, pp. A10-A21; Nelson, J. and Bradford, J. (1988): Late Paleozoic Marginal Basin and Island Arc Environments in the Sylvester Allochthon and Structural Framework of Mineralization in the Cassiar-Erickson Camp, Geology and Metallogeny of Northwestern British Columbia, Smithers Exploration Group - G.A.C. Cordilleran Section, Workshop Oct. 16-19, 1988, pp. A72-73; Clippings: Eileen East Vein, Drill Hole Intersections; Field visit notes, 1987; Cusac Gold Mines Ltd. Website (Apr. 1998): Cusac Gold Project, 3 p.; Cusac Gold Mines Ltd. (2001): Brochure and News Releases)
EMR MP CORPFILE (Cusac Industries Ltd.)
GSC MAP 381A; 1110A
GSC MEM 194; 319
GSC OF 2779
CMJ Dec. 1985; Feb.27, 2003; Feb.5, 2004
GCNL #242, 1978; #31,#120,#184,#209,#238, 1979; #199, 1980; #168,#237, 1981; #89,#149,#212, 1982; #20,#28,#87,#112,#137,#198, 1983; #225,#226, 1984; #68,#123,#193,#195, 1985; #19,#32,#50,#60,#126, 1986; #16,#31, 1987; #217, 1988; #170,#184, 1989; #35,#233, 1990; #22,#169, 1991; #63,#64,#245(Dec.21), 1992; #113(June 14), 1994; #52(Mar.14), #171(Sept.5), #202(Oct.21), #220(Nov.17), 1997; #47 (Mar.9), #160(Aug.20), #203(Oct.22), 1998
IPDM Jan.-Feb., 1983; Sept.-Dec., 1985
N MINER Mar.29, 1979; Apr., 1980; Feb.3, Jun.16, Jul.7,21, 1986; Feb.2, 1987; Dec.17, 1981; May 20, Aug.12, Nov.18, 1982; Feb.24, Aug.11, Oct.20, 1983; Apr.5, Dec.13, 1984; Oct.21, 1985; Feb.3, Jun.16, Jul.7,21, 1986; Feb.2, 1987; April 23, Dec.10, 1990; Nov.18, 1991; Jan.6, Apr.6, 1992; June 26, 1995; Oct.14, 1996; Apr.7, Sept.22, 1997; Mar.15, Apr.26, Jul.28, Aug.9, 2004; Jun.27, 2005
NAGMIN Jun.1, 1983
PR REL Cusac Gold Mines Ltd., July 10, Sept.3, Oct.17, 1997; May 25, 1999; Sept.20, 2002; Feb.19, Mar.12, Sept.25, 2003; Jan.12,29, Jun.8,29, Jul.28, Nov.8, 22, 2004; Feb.28, 2005; Oct.30 2007
V STOCKWATCH Jan.18, 1989
VAN M RPT Feb. 1987
W MINER Jun., 1982; Jun., 1983
Cusac Gold Mines Ltd. 1996 Annual Report
Dussell, E. (1986): Listwanites and Their Relationship to Gold Mineralization at Erickson Mine, British Columbia, Canada, M.Sc. Thesis, Western Washington University
Grant, D.R. (1981): A Study of the Sulphide Mineralogy and Geology of the McDame Gold Camp, Cassiar, British Columbia, B.A.S. Thesis, U.B.C.
Harms, T.A. (1986): Structural and Tectonic Analysis of the Sylvester Allochthon, Northern British Columbia, Implications for Paleogeography and Accretion, Ph.D. Thesis, University of Arizona
Wade, L. (1987): Gold and Its Relationship to the Mineralogy in the Eileen vein at Erickson Gold Mine, Cassiar, North-Central British Columbia, B.Sc. Thesis, U.B.C.