The Vigo prospect is located on the former Vigo (Lot 91) Crown grant, 1 kilometre due west of Treasure Mountain and 27.5 kilometres east-northeast of Hope, British Columbia.
Mineral showings in the area were first discovered in 1894 and known as the Treasure Mountain, Summit Camp, Silver Chief or Silver Hill property. Between 1894 and 1896, Indiana Company worked on the Sutter, Skyline, Lulu and Vigo claims. Sporadic exploration continued until 1913. The area has seen significant exploration and development work with production from 1920 to 1932 and then again in the 1950s. Since 1993, the Vigo prospect is owned by Golden Coast Minerals Ltd. In 1993, geological mapping and one trench was excavated at the Vigo prospect.
The Treasure Mountain region is underlain by northwest striking, moderate to steeply southwest dipping volcanic and sedimentary rocks of the Lower-Middle Jurassic Dewdney Creek Formation (Ladner Group) and Lower-Upper Cretaceous Pasayten Group, intruded by numerous dikes and sills. The Dewdney Creek Formation comprises volcanic rocks and a minor amount of sediments and consists of tuff, breccia and agglomerate with interbedded argillite and conglomerate. The Dewdney Creek Formation is considerably altered; pyrite is commonly present and many outcrops are rusty. The Pasayten Group includes predominantly arkose, argillite and conglomerate. Locally, the two sequences are separated by a northwest striking, northeast dipping fault, but in large part are conformable.
Mineral occurrences in the area are hosted in the Treasure Mountain fault and in and near subsidiary faults, and comprise one or more quartz-carbonate veins or stringers that branch and split and vary considerably in width and attitude (see Treasure Mountain, 092HSW016).
The Vigo occurrence is underlain by Dewdney Creek Formation massive conglomerate, tuff and thinly bedded argillite. A quartz- carbonate vein 10 to 15 centimetres wide striking 020 degrees and dipping steeply east, is exposed in a creek bed. It is mineralized with coarsely crystalline galena, minor sphalerite, chalcopyrite and pyrite.
Recent trenching has expanded this showing intermittently, both southwest along the creek for 120 metres and northeast for 50 metres from a vertical shaft. Several vein segments occur and probably occupy the same structure or closely related subparallel to parallel structures. Mineralization is variable and is consistently comprised of galena, sphalerite, chalcopyrite, pyrite, pyrrhotite, arsenopyrite with minor tetrahedrite, marcasite and antimony sulphosalts. The gangue includes quartz, calcite, siderite and silicified and chloritized wallrock fragments. The veins are called the Vigo, Falls, Lower Creek, Middle Creek and Upper Creek. One sample in the Middle Creek vein carries needle-like crystals in vugs, and surface coatings of jamesonite or boulangerite.
A summary of trench channel sampling of the veins are as follows. A weighted assay average of 18 samples along a 26 metre length of the Vigo vein with an average sample width of 0.64 metre, yielded 754.50 grams per tonne silver, 5.31 per cent lead, 13.55 per cent zinc, 0.90 per cent copper, 0.16 per cent antimony and 1.09 grams per tonne gold. A weighted assay average of 18 samples along a 17 metre length of the Falls vein with an average sample width of 0.24 metre, yielded 685.60 grams per tonne silver, 11.57 per cent lead, 10.75 per cent zinc, 0.57 per cent copper, 0.13 per cent antimony and 0.95 gram per tonne gold. A weighted assay average of 5 samples along an 8 metre length of the Lower Creek vein with an average sample width of 0.40 metre, yielded 375.70 grams per tonne silver, 2.57 per cent lead, 18.75 per cent zinc, 2.02 per cent copper, 0.05 per cent antimony and 0.78 gram per tonne gold. A weighted assay average of 6 samples along a 13 metre length of the Middle Creek vein with an average sample width of 0.50 metre, yielded 483.34 grams per tonne silver, 2.17 per cent lead, 23.93 per cent zinc, 2.76 copper, 0.3 per cent antimony and 1.57 grams per tonne gold. A weighted assay average of 6 samples along a 15 metre length of the Upper Creek vein with an average sample width of 0.49 metre, yielded 499.45 grams per tonne silver, 4.59 per cent lead, 10.79 per cent zinc, 0.65 per cent copper, 0.64 per cent antimony and 0.30 gram per tonne gold (Dewonck, 1987).
Trenching has also exposed two mineralized argillite bands which contain disseminations and bands of black sphalerite, pyrite, chalcopyrite, marcasite and pyrrhotite. A dump grab sample of stibnite from a filled-in trench, 30 metres south of the southernmost vein exposure (Upper Creek vein) identified as the Antimony Cut, assayed 47.9 per cent antimony (Dewonck, 1987).
Another quartz-carbonate vein, the Basil vein, has recently been discovered on the property (Assessment Report 18111) and has an average width of 30 centimetres. The vein strikes 064 degrees and dips 78 degrees north with an exposed strike length of 20 metres. It is mineralized with sphalerite with some galena and chalcopyrite and is hosted in an altered lithic crystal tuff. Sericite and epidote alteration mineralogy is present.
In 1993, the Cal vein was exposed by a new trench. The trench and vein are located immediately north of the Vigo claim near its northeast corner. The 23 metres of trenching exposed 21 metres of variable amounts of sphalerite, galena and chalcopyrite in a quartz vein. Mineralization is not restricted to the vein and extends along hairline fractures within massive, fine grained ash to lapilli tuff. The vein varies in width from 6 to 40 centimetres. The strike ranges from 040 to 072 degrees and dips range from 80 degrees southeast to vertical. The average strike is 058 degrees dipping steeply to the southeast. Chlorite alteration and silicification occur locally with in the hostrock. Manganese with minor limonite coatings occur along hairline fractures.
A total of 21 samples were collected from the trench. Samples yielded significant copper, zinc, lead and silver values. Seven samples yielded copper values ranging from 1.02 to 9.78 per cent copper. Corresponding lead values from these samples ranged from 0.90 to 2.53 per cent, zinc values ranged from 0.14 to 9.99 per cent, silver values ranged from 298.6 to 579.5 grams per tonne and gold values ranged from 0.82 to 1.18 grams per tonne (Assessment Report 23036).