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File Created: 02-May-1988 by Laura L. Coughlan (LLC)
Last Edit:  13-Feb-2020 by Garry J. Payie (GJP)

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NMI 104K11 Au1
Name JOLY, JAK, EUREKA TREND, LJ 1-4, 5-8 Mining Division Atlin
BCGS Map 104K075
Status Prospect NTS Map 104K11E
Latitude 058º 42' 46'' UTM 08 (NAD 83)
Longitude 133º 08' 31'' Northing 6509562
Easting 607629
Commodities Gold, Silver, Zinc, Lead, Antimony, Copper Deposit Types I05 : Polymetallic veins Ag-Pb-Zn+/-Au
Tectonic Belt Intermontane Terrane Stikine, Cache Creek
Capsule Geology

The Joly showing occurs along the Eureka Trend. The main lithological units recognized near the Joly-Jak Showing are from the Upper Triassic King Salmon Formation, part of the younger Upper Triassic Stuhini Group and a diorite/monzonite intrusion. In addition a major anticline, the King Salmon Anticline, plunges gently to the northwest near the Taku River and gently southeast near the Joly-Jak showing along a 115 degree trend. The King Salmon Formation rocks are comprised primarily of thinly-laminated, grey to bluish grey mudstone and siltstone.These rocks are slightly to moderately limey and are typically hornfelsed.

Within the upper portions of this sequence, there are either recrystallized greywackes or felsic volcanic or subvolcanic rocks with low angle, thinly laminated bedding. Locally, these units contain ellipsoidal patches, up to 2 centimetres in diameter, of medium to coarse grained calcite with numerous patches of pyrite and sphalerite. A thick andesite interlayered with massive greywacke(?) and thinly- to thickly-bedded arenite with 30 centimetre thick lenses of limestone can be found lower down in the stratigraphic sequence. These bedded rocks strike 120-135 degrees, dip 40-45 degrees southwest along the southwest limb of the King Salmon Anticline and are relatively uniform.

Two phases of intrusive rocks were found to cut the sedimentary rocks within this area: at the head of Joly Creek and southwest above Jak Creek. The intrusive rock at the headwaters of Joly Creek cuts irregularly across the sedimentary rocks and consists of a white, slightly porphyritic dacite containing 1-3 per cent disseminated pyrite. This unit, as well as the sedimentary rocks, are cut by several sheeted fine to medium grained, carbonate altered diorite-syenodiorite dikes of up to 3 metres across. These dikes trend parallel to the east-west fracture system. The Jak Creek intrusion is a strongly calcite-, iron-carbonate-, muscovite/sericite-altered medium-grained diorite/monzonite(?) stock. This unit is typically orange-brown along the weathered surface due to the release of iron from the iron-carbonate. A contact of the Jak Creek intrusion with the sedimentary rocks is exposed along the upper portion of Jak Creek. At this contact, a one to two metre wide zone of massive coarse-grained carbonate, with a tightly folded (within a few metres) laminated mudstone and siltstone unit, occurs within a steeply dipping planar zone and is interpreted to be a fault zone.

Within the Eureka Trend numerous sheeted sulphide veins have been identified. Veins have been observed in outcrop across strike for over 100 meters and along strike for over 650 meters and remains open in all directions. Gold mineralized veins are continuous, forming near vertical sets within a regional east-west trending fault zone. The zone forms a topographical linear extending for over 10 kilometers along strike. Mineralized bedrock exposures have been discovered in vertical relief greater than 370 meters. Veins are hosted in a rusty-weathering fine grained quartz diorite with slight argillic alteration and consist of massive arsenopyrite with lesser pyrite, galena, stibnite and sphalerite with individual widths up to 0.5 meter. Smaller, up to 5 centimeter wide, arsenopyrite-pyrite-quartz veins form splays and offshoots with sulphide lenses and disseminated pyrite in altered wall rock.

J2 Syndicate reported in 2016 that rock samples yielded up to 34 grams per tonne gold, 1210 gram per tonne silve, 3.92 per cent copper, 9.17 lead and 4 per cent zinc (Assessment Report 37087, Appendix C report by Turna and Goeppel, 2017), Figure 8).

Bedded rocks on the property strike between 120 to 135 degrees and dip 40 to 45 degrees southwest. The rocks are strongly fractured with two major, steeply dipping sets, one striking 090 degrees and the other striking between 130 to 150 degrees.

Near the headwaters of Joly Creek, there is a broad zone of carbonate alteration which hosts many quartz-carbonate veins averaging 5 to 10 centimetres across (maximum 30 centimetres) with a spacing of every few metres. The veins are fracture fillings in the 090 degree fracture set between elevations 1000 to 1350 metres.

Veins at the headwaters of Jak Creek, between elevation 975 and 1040 metres, infill mainly the 130 degree fracture set within strongly altered porphyritic andesite.

The fracture filling veins host patches and lenses of sulphides in a gangue of quartz and calcite. The sulphides, in order of decreasing abundance, consist of pyrite, arsenopyrite, sphalerite, with minor galena, stibnite, pyrrhotite, and chalcopyrite. In 1980, a sample from an arsenopyrite-sphalerite-pyrite-galena vein returned 1.7 grams per tonne gold, 102.89 grams per tonne silver, 1.9 per cent lead, 8.3 per cent zinc, and 7.5 per cent arsenic. Another sample from the lower Jak Creek showing assayed 17.8 grams per tonne gold, 579.4 grams per tonne silver, 6.23 per cent lead, 2.55 per cent zinc, 0.65 per cent arsenic, 0.42 per cent copper, and 2.53 per cent antimony (Assessment Report 9048).

There is a major shear with associated intense fracturing in the lower Jak Creek area. The shear is associated with strong pyritic alteration and hosts pyrite veins, averaging 1 to 2 centimetres in width, containing minor associated sphalerite, stibnite, chalcopyrite, and galena. This mineralization is thought to be the eastern extension of the mineralized shear and/or fracture system, located on the Go claims (104K 074).

WORK HISTORY

The following Work History discusses history in a more regional context and provides further details of work done on the Joly occurrence. The work areas are referenced to the 2004 LJ claim group of Rimfire Minerals in order to provide a locational context; refer to Rimfire Assessment Report 27589.

The earliest recorded work in the area was carried out in 1980 by Anglo-Canadian Mining (Assessment Report 9048), who discovered the Joly showing (104K 090), a broad zone of carbonate alteration hosting a number of 5-10 centimetres calcite-quartz-sulphide veins trending 090 degrees. Soils, silts and more than 23 rock samples were collected. Their best sample from the Joly showing assayed 1.7 grams per tonne gold, 271 grams per tonne silver, 1.0 per cent lead and 9.6 per cent zinc. The Jak showing (104K 090), 600 metres to the southeast, consists of an intensely fractured (main sets at 090 degrees and 150 degrees) and altered zone, with 1-2 mm pyritic veins along most fractures of both sets. A few veins contain sphalerite, stibnite, chalcopyrite and galena. The best sample reported by Anglo-Canadian from the Jak showing (104K 090) assayed 17.8 grams per tonne gold, 579 grams per tonne silver, 6.23 per cent lead, 2.55 per cent zinc, 2.53 per cent Sb, 0.65 per cent arsenic and 0.42 per cent copper.

Joly and Jak occur on Rimfire's LJ 1-4, 5-8 claims in 2004 (Assessment Report 27589).

Also in 1980, Comaplex Resources International and Redfern Resources collected regional silt samples over much of the Tulsequah map-sheet, identified an anomaly immediately west of Anglo-Canadian’s ground and discovered gold-bearing arsenopyrite veining there.

On the Go claim (MINFILE 104K 074), a porphyry stock is cut by east-west faulting and carbonate alteration over a 100 metres width. Conjugate fractures to the faulting are mineralized with arsenopyrite, pyrite, pyrrhotite, chalcopyrite, galena, sphalerite and stibnite. Six trenches and 973 metres of diamond drilling in 9 holes were completed in 1981. Drilling confirmed that the mineralizing system continues along a strike length of greater than 205 metres and a down-dip length of greater than 150 metres. Precious metal mineralization was narrow and spotty (best intersection: 0.13 metres at 7.1 grams per tonne gold and 514 grams per tonne silver (Assessment Report 9495).

In 1988, Georgia Resources Inc. worked the LIS 2 mineral claim, collecting 61 soils. (This area is part of the 2004 LJ 7, 8 claims of Rimfire Minerals as defined in Assessment Report 27589.) This program worked the showings known as the Jak and Joly (104K 090) (described above) and extended the limits of the veins further to the east. Maximum values reported in the anomalous soils from a single sample were 0.452 parts per billion gold, 19.2 ppm silver, 0.91 per cent arsenic, 84 parts per million antimony, 0.1 per cent copper, 0.047 per cent lead and 0.056 per cent zinc (Assessment Report 17517).

In 1990, Solomon optioned the LJ mineral claim from Cominco Ltd. and collected 167 soils, 2 silts and 25 rocks. (This area is part of the 2004 LJ 20 claims of Rimfire Minerals as defined in Assessment Report 27589.) Cominco previously reported grades from chip samples of quartz-arsenopyrite veins of 22.4 grams per tonne gold over 1 metre, 40 grams per tonne gold over 0.2 metre and 10.4 grams per tonne gold over 0.25 metre. These grades were not reproduced by Solomon. However, Solomon did identify two zones of mineralization. Zone 1 is hosted in a 150 metres long fault zone trending 178 degrees and consists of 2-5 per cent pyrite-arsenopyrite veins. An average of 16 grab samples gave 0.14 gram per tonnes gold, 0.78 gram per tonne silver and 0.63 per cent arsenic from zone 1 (Assessment Report 20433). Zone 2, located 750 metres to the northeast of zone 1, is characterized by quartz-arsenopyrite-pyrite veins hosted in shears and fault zones trending 110 -140 degrees. Five grab samples from this zone returned average grades of 0.9 gram per tonne gold, 1.46 grams per tonne silver and 0.31 per cent arsenic (Assessment Report 20433). Soil samples from this program suggest that these mineralized zones have limited widths and that the most prospective ground may be located to the west of the area worked.

In 1991 Georgia Resources Ltd. conducted a geophysical program as follow-up to the mapping and sampling the previous year. 2.7 kilometres of VLF-EM were surveyed to the southeast of the Joly and Jak showings (104K 090). This survey defined a weak east-west trending anomaly which coincides with the known Joly showing (Assessment Report 21435).

In 1991, Solomon Resource Ltd. conducted a geological mapping and geochemical program on the Wahb property (104K 150) collecting 89 soils and 36 rocks (Assessment Report 21522). (This area is parts of the 2004 LJ 9-12 claims of Rimfire Minerals as defined in Assessment Report 27589). Two main mineralized zones occur at the top of Mount Lester Jones just north of the main peak. Zone 1 is a 250 metres long by 5 metres wide shear/fault zone which contains several thin massive arsenopyrite-stibnite veins (maximum width 0.25 metres). These steeply dipping, NW trending veins returned maximum assays of 1.5 grams per tonne gold and 309 grams per tonne silver (Assessment Report 21522). A second zone trending the same directions as zone one is located 300 metres to the northeast of zone 1 and is exposed for 50 metres, with maximum assays of 2.7 grams per tonne gold and 309 grams per tonne silver (Assessment Report 21522). Both of these zones are covered by a large glacier at the top of Mount Lester Jones along strike of the exposures.

In 1992, Georgia Resources Inc. returned to the Jak and Joly showings (104K 090) and collected 70 soil, 22 silt and 22 rock samples and conducted a mapping program (Assessment Report 22384). (See 2004 claims LJ 1-8 of Rimfire Minerals Corporation in Assessment Report 27589). The program confirmed the presence of precious metal mineralization in Jak Creek with a maximum assay of 5.9 grams per tonne gold and 351 grams per tonne silver (Assessment Report 22384). During this program the mountain directly south of the Jak and Joly showing was prospected.

In 1998 Xplorer Gold Corp surveyed a total of 7.65 line kilometres of horizontal loop-EM and total magnetic field on three areas (Assessment Report 25458, 25459, 25460) on the future 2004 LJ claims of Rimfire Minerals (as indicated in Assessment Report 27589). The purpose of these surveys were to identify potential VMS targets, however none of the data returned anything that would indicate this potential.

During June 2004, Rimfire initiated a regional geological mapping, prospecting and soils and silt sampling program on the LJ and Sutlahine claims, collecting 85 rock samples, 92 silt samples and 504 silt samples (Assessment Report 27589). Fault hosted gold-silver bearing quartz-galena-sphalerite-arsenopyrite veins were re-examined in Jak and Joly creeks and extended beyond their previously known extents. Additionally, veins that are similar to the Jak and Joly showings were discovered north of the known showings. These veins are hosted in steeply dipping normal faults and fault zones (approximately 10 metres wide) that trend 270 degrees. Fault zones host several veins that trend parallel to the fault zone; the maximum observed width of these veins was 20 centimetres. Disseminated sulphides are present between veins within the fault zones. A thin envelope (2-5 metres) of carbonate-clay-sericite-(plus/minus silica) alteration surrounds the veins and rapidly grades outwards to an alteration assemblage characterized by chlorite, clay, with lesser sericite. Gangue mineralogy is dominated by quartz and carbonate. Sulphide mineralogy is dominated by variable amounts of pyrite, galena, sphalerite and arsenopyrite with lesser or trace amounts of chalcopyrite, pyrrhotite and sulphosalt. Base metal rich carbonate veins were also encountered by Rimfire along the bank of Rickards Creek between Jak and Joly creeks. Directly to the east of these veins in Keiths Creek two meter-scale carbonate-pyrite-sphalerite-galena vein outcrops, whose margins aren’t exposed, were discovered. These outcrops are located approximately 15 metres apart. It is unclear if the carbonate veins in Rickards are related to the zone of massive carbonate in Keiths Creek.

In 2005, Barrick Gold Incorporated explored its large claim holdings (including the Sutlahine claims of Rimfire Minerals) that extended from Tatsamenie Lake northwest to the Taku River. The property covered a 70 by 20 kilometres area. Barrick collected 848 rock, 46 stream sediment and 46 stream sediment samples. Results from the field season were considered poor.

In 2016 J2 Syndicate Holdings conducted a reconnaissance exploration program over three days in August of 2016 prior to staking the Eldorado Property. A total of 15 rock grab samples were collected on the following: the Joly and Jak showings where a chip sample graded 17.85 grams per tonne gold and 108 grams per tonne silver; the new Cash showing where a sample from mineralized stockwork within a siliceous fault graded 0.49 grams per tonne gold and 1.16 per cent lead ; and the Bonanza showing, located southeast of the historical WAHB showing, assayed 2.18 grams per tonne gold, 149 grams per tonne silver, 5.31 per cent lead (Appendix C, Assessment Report 37087).

The 2017 exploration program was carried out on the Eldorado Property from August 26th to August 31st, 2017 and consisted of reconnaissance and follow-up prospecting, mapping, silts and rock sampling (Appendix C, Assessment Report 37087). One hundred and nine (109) samples were taken: 21 chip samples, 36 rock grab samples, 45 talus fine samples and 7 silt samples. Two geologists and one prospector traversed the property collecting samples, geological observations and pictures.

Bibliography
EMPR ASS RPT *9048, 9495, *17517, 20433, *21435, 21522, *22384, 25458, 25459, 25460, *27589, *37087
EMPR EXPL *1980-491
EMPR FIELDWORK 1985, pp. 175-183; 1986, p. 103; 1992, pp. 159-188; 1992, pp. 159-176, 177-183
EMPR OF 1993-1; 1993-11; 1995-21; 1996-11
GSC MEM 248; 362
GSC MAP 6-1960; 931A; 1262A
GSC P 45-30
GCNL #173, 1980; #13,Jan.,#84,May4, 1981

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