This occurrence area comprises poly deformed and metamophosed volcanics, volcaniclastics, sediments, and intrusives of the Upper Paleozoic Stikine assemblage. Upper Triassic volcanics and sediments overlie these unconformably to the northwest and are intruded by several plutonic units of batholithic size. The Paleozoic rocks have undergone a high degree of metamorphism and four phases of folding, which combined have transformed these rocks into a variety of schists and phyllites. A unit described as greenstone and foliated greenstone on the property along with a dioritic rock, which is observed grading to foliated greenstone. Several distinct types of mineralization are hosted by these rocks.
Upper greenschist to lower amphibolite metamorphism has produced metamorphogenic quartz veins which are weakly pyritized and contain some chalcopyrite. Silica-potassic alteration peripheral to these veins is common. A telluride vein, exposed over 180 metres, is host to a mineral assemblage including gold, hessite, tetradymite, tellurobismuthite, galena, tetrahedrite, sphalerite, chalcopyrite and pryite. Vein margins are indistinct and show increasing silicification of wall rocks. Gold values are low with a high of 0.48 gram per tonne.
A second type of mineralization is hosted by quartz breccia veins. These are easily distinguished because they carry fragments of silicified wallrocks. They are mineralized with pyrite, galena and sphalerite, as well as gold within a fine-grained glassy quartz and barite matrix. This zone of veining occurs at the contact between quartz-sericite schist and metavolcanics along a strike length of at least 450 metres. Gold values from channel samples range up to 30.27 grams per tonne over 1.5 metres. Quartz-chalcopyrite veins which are contemporaneous with the quartz breccia veins occur exclusively within iron-carbonate alteration zones. These narrow, sinuous veins also carry minor tetrahedrite.
Carbonate-sulphide veins with associated sericite and carbonate alteration contain massive to granular pyrite and arsenopyrite and scattered coarse blebs of sphalerite, chalcopyrite and galena in a siderite matrix. Gold mineralization is erratic but samples contain highs of up to 0.34 to 2.06 grams per tonne.
Sulphides are also found in ubiquitous carbonate alteration zones that are confined to massive chlorite schists and greenstones.
Disseminated pyrite is common, along with lesser arsenopyrite. Gold grades range from 1.0 to 3.1 grams per tonne.
A significant north-south trending zone of quartz-breccia veining containing sulphides was drilled in 1988. This zone appears to be hosted within quartz-sericite schist and green metavolcanics.
Work History
The BJ claims were staked in 1980 as the follow-up to a regional stream geochemical survey. Although indications of earlier prospecting were found there is no record of any previous claims having been staked in the area. Work in in 1980, 1981, 1982 and 1986 by Teck Corporation consisted of various geochemical surveys, trenching and geological mapping. During the program of 1986 a gold-bearing vein on the Windy claim was discovered which prompted a programme of hand trenching and sampling. Prospecting in the vicinity of the vein discovered in 1986 located an additional six mineralized structures. Hand trenching to expose the veins was followed by chip sampling and mapping. A total of 45 trenches to bedrock were dug for a total of 398 linear metres.
