The UM vein is up to 2.5 metres wide hosted by a northwest trending linear peridotite and consists of a zone of quartz-carbonate alteration and stringers containing trace pyrite and chalcopyrite with some fuschiste/mariposite evident. The vein is located in a listwanite alteration zone of an ultramafic lens that is part of an Early Jurassic unit near the contact with greenstone and greenschist of the Devonian to Middle Triassic Boundary Ranges Metamorphic Suite. The lens trends northwest, occupies a structural break and dips steeply to the southwest and northeast. The vein has been isolated over 700 metres of strike length and, from a total of 15 rock chip samples, averages 3.77 grams per tonne gold and 45.59 grams per tonne silver (Assessment Report 20790). In 1993, rock chip sampling across 2.5 metres of the UM vein yielded 3.9 grams per tonne gold (Assessment Report 23149).
Features of the UM vein that show it to be mesothermal include its association with a major fault, a strong ferroan carbonate-mariposite alteration of mafic to ultramafic hostrocks, crosscutting quartz veins, and characteristic orange-brown limonite weathering. It also has a higher than usual silver:gold ratio.
Work History
The UM vein was part of the Teepee property to the southeast of the TP showings (104M 048-050) and the Crine veins (104M 081) near Teepee Peak about 54 kilometres west of Atlin. Refer to the TP-Main showing for details on the property.
The Teepee Peak property hosts several gold-bearing vein and skarn showings which have been the focus of exploration work by Cyprus Gold between 1988 and 1990. The Add 1-8 claims were staked to cover prospective ground following the discovery of the "UM" vein in 1990. In 1990, trenching, diamond drilling, prospecting and sampling were conducted on the Crine veins and the UM vein located on the newly staked Add 3 claim. In 1993, work was conducted on the Add claims by Noranda Exploration Company, Limited on behalf of Hemlo Gold Mines Inc. Hemlo conducted work on the property under the terms of an option agreement with Cyprus Gold in effect during 1993. Work consisted of the establishment of a small picketed grid and 182 soil samples were taken in addition to 71 rock samples.
In 2011, Blind Creek Resources collected 30 soil and 3 rock samples east of the Um prospect in order to trace it in that direction. Several soil samples yielded weak metallic geochemical responses, none of which were grouped and were not considered significant.
In 2012, a three man team, on behalf of Blind Creek Resources, collected 75 rock grab samples and 22 soil samples over a 700 metre wide listwantite system. Out of the 75 rocks values were no greater than 4.4 grams per tonne gold and 22.9 grams per tonne silver (Assessment Report 33470). The results were not considered significant enough to continue with Um as a priority target.