The Silver Pond (West) occurrence is located at an elevation of approximately 1700 metres on a southwest-facing slope, northeast of Notary (Silver) Creek and approximately 8.5 kilometres southeast of the junction of Lawyers Creek and the Toodoggone River.
The Lower Jurassic Toodoggone Formation (Hazelton Group) volcanic rocks form a northwest-trending belt, at least 90 kilometres long and 35 kilometres wide, preserved between undivided Lower to Middle Jurassic Hazelton Group rocks to the east and the Upper Cretaceous to Eocene(?) Sustut Group rocks to the west. Where observed, they rest structurally on Upper Triassic Takla Group rocks.
Toodoggone pyroclastic and epiclastic volcanic rocks are a predominantly calcalkaline andesitic to dacitic subaerial succession. The region as a whole resembles a synclinorium in section from northwest to southeast. Potassium-argon studies of hornblende and biotite indicate the age of Toodoggone volcanism ranges from 204 to 182 Ma. This age appears to be divisible into two main groups: an older, lower stage of volcanism dominated by andesitic pyroclastics and flows characterized by widespread propylitic and zeolitic alteration; and a younger, upper stage of volcanism dominated by andesitic ash-flow tuffs which generally lack significant epithermal alteration. All the known epithermal gold-silver deposits and occurrences are restricted to the lower Toodoggone Formation volcanics and underlying units (Fieldwork 1988).
Toodoggone volcanic rocks display broad open folds or homoclines with attitudes generally less than 25 degrees dipping predominantly to the west. The overlying Sustut Group sedimentary rocks are structurally unaffected and are horizontal. A northwest trending set of younger, steeply dipping faults and synvolcanic half-graben margins are the dominant structure in the region. Major structural breaks are postulated to have been caused, or be the result of, a northwest trending line of volcanic centres. Small stocks are also aligned northwest, suggesting they were also influenced by the same structural trend. Subsequent to volcanism and intrusion, young faults are recognizable as northwest-trending lineaments. Major north-northwest fault systems are from west to east: Attorney; Moosehorn-McClair; and Saunders-Jock. Most prominent gossans are aligned along this configuration of faults. The Attorney fault system passes through the Lawyers property (094E 066).
Two distinct mappable sequences of the Toodoggone volcanics, consisting of an older pyroclastic quartz andesite crystal tuff sequence (Adoogacho Member) and a younger trachyandesite sequence (Metsantan Member), are evident on the Silver Pond property. These volcanics strike northeast and dip 5 to 20 degrees to the northwest. The two sequences are intruded by steeply dipping rhyolite to rhyodacite dikes and are generally associated with steeply dipping fault zones. These are overlain by pyroxene basalt. The volcanic sequence in stratigraphic order is composed of, (1) quartz andesite crystal tuff, (2) fine grained to aphanitic chocolate brown tuff, (3) welded trachyte tuff, and (4) trachyte crystal and crystal lapilli tuff with interbedded volcanogenic greywacke. Several north-northwest striking faults have been identified and are slightly offset by younger east-striking faults. The north-northwest striking faults apparently were the conduits for the mineralizing fluids which gave rise to mineralization at the Silver Pond (North) (094E 069), Silver Creek (094E 075), Amethyst (094E 160), South (094E 161) and Ridge (094E 162) prospects. The Toodoggone volcanics are affected by widespread weak propylitic alteration and weak silicification.
The southern portion of the Silver Pond property is capped by younger Sustut Group conglomerates in slight angular unconformity with the underlying Toodoggone volcanics.
Alteration associated with structurally controlled epithermal mineralization, in the area, consists of pervasive silicification grading outward into weaker silicification, sericitization, and argillic and potassic alteration. An alteration zone, two kilometres across, covers much of the area and is marked by a gossan of abundant goethite, jarosite and hematite. Quartz, alunite, kaolinite, montmorillonite, dickite, illite, sericite, and minor amounts of barite, fluorite, limonite and pyrite comprise secondary minerals in intermediate to advanced argillic-altered zones (Forster, 1984).
Two general styles of acid-sulphate type epithermal gold-silver mineralization occur on the Silver Pond property. These consist of vein and breccia-type ore shoots and pods, such as the Silver Pond (West) prospect and the Silver Pond (Silver Creek) prospect (094E 075); and high-level stockwork-type mineralization such as the Silver Pond (North) prospect (094E 069). Gold and silver are generally absent from intensely altered regions in the area, with pyrite and magnetite being the only visible metallic minerals (Forster, 1984).
The Silver Pond (West) deposit constitutes part of a regional northwest to north-northwest striking fault zone, west of and parallel the Cliff Creek fault. Hostrocks for the mineralization are porphyritic andesite flows, agglomerates, and crystal and lapilli tuffs. Propylitic alteration is characterized by chlorite and pyrite replacement of the original mafic minerals and epidote and albite replacement of igneous plagioclase. Alteration associated with mineralization includes strong to pervasive silicification, sericitization, and potassic and argillic alteration.
The mineralized zone is hosted in a wide alteration zone. At least three 1- to 3-metre-wide auriferous zones of intense silicification, brecciation and minor amounts of sulphide characterize mineralization within this alteration zone. All three auriferous zones are parallel, striking 120 degrees with a subvertical dip and separated by 10 to 30 metres. The most intense mineralization and alteration occur as an up to 40-metre wide stockwork zone in both the hangingwall and footwall of a vertical to steeply southeast or northeast dipping rhyolite dike. The dike is partially altered at its contacts and is in places cut by stockwork-type mineralization. Mineralization and alteration intensity of the rhyolite dike to the northwest and southeast decrease significantly.
Two types of mineralization are recorded: (1) narrow veins and stringers of multistage silica with minor calcite, epidote, chlorite, pyrite and laumontite, rare amethystine quartz with traces of galena, chalcopyrite, sphalerite, electrum, native silver and acanthite; and (2) zones of intensive to pervasive silicification which are usually associated with hydrothermal brecciation and intense multiphase veining.
Work History
The Silver Pond property was originally staked by Chuck Kowall in 1979 and 1980 to cover two gold-silver occurrence and associated geochemical anomalies identified by Kennco in the 1970s. In 1981, Great Western Petroleum Corp. optioned the Silver Pond claims and the following year completed a program of soil and rock sampling and geological mapping. In 1983, St. Joe Canada Inc. optioned the claims and formed a joint venture with Imperial Metals Corp. and completed a program of prospecting, geological mapping, geochemical sampling and trenching.
The Silver Pond West zone was identified in 1984 when mineralized quartz-bearing talus was identified on the east side of Cloud Creek. Follow-up geochemical and geophysical surveys conducted later that year defined a 600-metre long northwest trending gold-in-soil anomaly and a coincidental magnetic low and partly coincidental resistivity high. Trenching on a resistivity high uncovered a zone of quartz breccia yielding 9.0 grams per tonne gold and 24.2 grams per tonne silver over a width of 5.0 metres (Lane, R.A. (2018-04-30): NI 43-101 Technical Report and Resource Estimate on the Lawyers Gold-Silver Project).
In 1985, St. Joe completed a program of trenching and 29 diamond drill holes, totalling 3003 metres. Nineteen of the drill holes were completed on the Silver Creek (MINFILE 094E 075) zone, three holes on the Silver Pond South zone (MINFILE 094E 161), two holes on the Silver Pond Amethyst zone and four holes were completed on the West zone. The best intersection from the West zone came from hole SP-85-26 and yielded 0.97 gram per tonne gold and 6.0 grams per tonne silver over 21.00 metres, including 8.07 grams per tonne gold and 9.9 grams per tonne silver over 2.0 metres (Assessment Report 14700). Also in 1985, a trench (W5) located approximately 200 metres southeast of the zone being drilled yielded 9.00 grams per tonne gold and 24.19 grams per tonne silver over 9.0 metres (Assessment Report 14700).
The Silver Pond (West) developed prospect was the focus of an extensive drill program in 1987, consisting of 6011 metres in 55 holes. Diamond drilling intersected gold mineralization over a strike length of over 400 metres and a depth of 200 metres vertical. Significant intercepts range up to 12.3 grams per tonne gold and 324.4 grams per tonne silver over a true width of 2.12 metres (Assessment Report 16952). A total of 70 significant intercepts with over 1 gram per tonne gold and silver were recorded. The weighted average of these intercepts was 3.29 grams per tonne gold and 23.24 grams per tonne silver over 1 metre true width (Assessment Report 16952). Several reserve calculations have been made. Two gold reserve calculations are quoted here (Assessment Report 16952).
---------------------------------------------------------------------- | TONNAGE | AVERAGE GRADE | TONNAGE | AVERAGE GRADE ZONE A | 27811.80 | 7.19 | 34806.60 | 6.23 ZONE B | 7464.00 | 5.37 | 14683.30 | 4.07 ZONE C | 12543.80 | 6.96 | 12611.30 | 6.94 TOTAL | 47819.60 | | 62101.20 | AVERAGE GRADE | 6.85 g/t | 5.86 g/t AVERAGE TRUE WIDTH .40 metres | 1.34 metres CUTOFF GRADE 3.0 g/t and 3.6 GMP* 2.4 g/t and 2.88 GMP* * GM Product (gold equivalent (grams/tonne) x thickness (metres) ---------------------------------------------------------------------- |
The apparent lack of vertical and along-strike continuity accounts for the low tonnage.
An area of coincident resistivity and magnetic high, southeast of the Silver Pond (West) occurrence, was tested by backhoe trenching in 1987. Further precious metal mineralization was not uncovered.
In 1988, Bond Gold Inc and Nexus Resources Corp. completed a program of diamond drilling on the Amethyst, Silver Creek, West and North zones of the Silver Pond property, totalling 3729 metres in 17 holes.
In 1992, Even Resources Ltd. optioned the property and explored the northeast portion of the North (MINFILE 094E 069) zone grid with a program of excavator trenching and local blasting.
In 1994, Ocean Crystal Resources Ltd. completed a program of geological mapping, trenching, an induced polarization survey and nine diamond drill holes, totalling 522.8 metres, on the area northwest of the West zone and southeast of the North (MINFILE 094E 069) zone. Trenching encountered 12 quartz veins in areas of intense argillic alteration, while drilling intersected three un-mineralized structures.
In 2000, Guardsmen Resources Inc. acquired the property, and the following year completed a program of rock sampling, geological mapping and ground electromagnetic and magnetic surveys on the area. Samples from the West zone yielded from 0.02 to 3.86 grams per tonne gold and 0.6 to 26.8 grams per silver, whereas a sample from a southeast-striking and 70 degree southwest-dipping chalcedony-quartz vein with argillic alteration, located north of the West zone, yielded 0.17 gram per tonne gold and 11.6 grams per tonne silver (Assessment Report 26728).
In 2003, Guardsmen Resources completed a further program of rock and soil sampling, trenching and 7.9 line-kilometres of ground magnetic and electromagnetic surveys on the area.
In 2003, P. Hawkins, P.Eng., prepared resource estimates in a report dated June 27, 2003, entitled "A technical report covering the Lawyers and Al (Ranch) properties for Bishop Resources Inc., Toodoggone River area, Omineca and Liard mining divisions, B.C.," a copy of which was filed via SEDAR by Bishop Gold Inc. on Feb. 6, 2004. Inferred resources at Silver Pond were stated at 62,100 tonnes grading 5.86 grams per tonne gold at a cut-off of 2.4 grams per tonne gold equivalent (the gold equivalent factor of 1:93 (Au:Ag) and $400 (U.S.) per ounce gold were used for the Lawyers) (Press Release - Bishop Gold Inc., February 15, 2005).
In 2004, Bishop Gold Inc completed a large trenching program on the former Lawyers epithermal gold-silver property. The company focused its program on the plateau west of the Cliff Creek portal on the M Grid of South (MINFILE 094E 161) zone, where prospecting in 2003 located high-grade gold-silver vein float. Trenching exposed four zones of epithermal quartz veining, brecciation and silicification, 1 to 10 metres wide, over a northwest-trending strike length of approximately 400 metres.
In 2018, Benchmark Metals Inc. and PPM completed a program of geochemical (rock and soil) and biogeochemical sampling, a 1272 line-kilometre airborne radiometric survey, eight diamond drill holes, totalling 1493.0 metres, and 30 rotary drill holes, totalling 2623.0 metres. This work focused along the Layers (MINFILE 094E 066) mineralization trend, which is greater than 3 kilometres long. Two rock samples (Y445227 and Y445226) taken from a 1-metre-wide massive quartz vein, located in a steep gully approximately 400 metres northwest of the West zone, yielded 0.201 and 0.209 gram per tonne gold with 15.4 and 26.7 grams per tonne silver (Assessment Report 38447). The vein strikes from 110 to 130 degrees and dips near vertically.
In 2019 and 2020, Benchmark Metals Inc. completed programs of geochemical (rock and soil) and biogeochemical sampling, ground and airborne geophysical surveys, 242 diamond drill holes, totalling 69 080 metres, and 191 reverse-circulation drill holes, totalling 28 395 metres, on the area as part of the Lawyers property. The majority of the drilling targeted the Cliff Creek, Dukes Ridge, Phoenix and AGB zones of the Lawyers (MINFILE 094E 066) deposit but nine holes were competed on the Silver Pond occurrences.
