British Columbia Ministry of Energy, Mines and Natural Gas and Responsible for Housing
News | The Premier Online | Ministries & Organizations | Job Opportunities | Main Index

MINFILE Home page  ARIS Home page  MINFILE Search page  Property File Search
Help Help
File Created: 24-Jul-1985 by BC Geological Survey (BCGS)
Last Edit:  31-Mar-2022 by Karl A. Flower (KAF)

Summary Help Help

NMI 093B9 Cu1
BCGS Map 093B059
Status Developed Prospect NTS Map 093B09W
Latitude 052º 31' 42'' UTM 10 (NAD 83)
Longitude 122º 18' 53'' Northing 5820024
Easting 546489
Commodities Copper, Gold, Silver, Zinc, Molybdenum Deposit Types L04 : Porphyry Cu +/- Mo +/- Au
Tectonic Belt Intermontane Terrane Cache Creek, Quesnel
Capsule Geology

The Gibraltar-North is located near the eastern margin of the Stikinia Terrane west of Granite Mountain in south central British Columbia. The dominant rock types in the region are metabasalt, limestone and argillaceous metasediments of the Mississippian to Triassic Cache Creek Group. These are intruded by the dioritic to quartz dioritic Granite Mountain Pluton and the (?)Cretaceous Sheridan Creek Pluton. The Granite Mountain Pluton has been affected by regional metamorphism (greenschist facies) and deformation along with the enclosing Cache Creek Group.

The Jan-Summit showing consists of a zone of chalcopyrite and molybdenite mineralization hosted in quartz diorite of the Granite Mountain Pluton towards its western margin.

Samples from drilling in the central area of the Jan and Summit claim groups in 1991 averaged 3.4 grams per tonne silver and copper assayed up to 0.82 per cent over 93 metres (George Cross News Letter #153, Aug. 9, 1991).

In 1991, the East Stage III pit from Gibraltar mines will be extended to the east end of the Summit claims.

Deep but high-grade ore was discovered in a large shear zone in a new orebody called Gibraltar North. Unlike the other orebodies, this has no significant molybdenite, but has significant zinc and precious metals. The new zone is located 2 kilometres northwest of Gibraltar East (093B 012). Recent drilling extended the strike length of the zone to the northwest as well as to the southeast bringing its total strike extent to about 914 metres. The zone measures 121 to 152 metres wide and 91 to 106 metres in thickness (Northern Miner - October 5, 1992). Indicated reserves are 40 million tonnes grading 0.4 per cent copper (Information Circular 1992-1).

Reserves for the Gib-North deposit stated in 1993 are 45,355,000 tonnes grading 0.4 per cent copper, using a 0.18 per cent copper cutoff, available to a 2.7:1 waste-to-ore stripping ratio (John A. Chapman). As of December 31, 1992 geological resources are estimated at 92,714,300 tonnes of 0.365 per cent copper (CIM Special Volume 46, page 202).

On February 12, 1993, Gibraltar Mines Limited announced that it would not proceed with development of the Gib-North deposit (Property File - Briefing notes from a mine tour on February 12, 1993, Rick Meyers, Kamloops District Geologist).

In 2019, an updated resource estimated was released for the Gibraltar mine with a measured and indicated resource of 1 109 000 000 tonnes grading 0.25 per cent copper and 0.007 per cent molybdenum and an inferred resource of 59 000 000 tonnes grading 0.21 per cent copper and 0.004 per cent molybdenum (Weymark, R. [2019-11-06]: Technical Report on the Mineral Reserve Update at the Gibraltar Mine, British Columbia, Canada).

See 093B 012 for a more detailed geological description of the Gibraltar mine and area.

EMPR ASS RPT 618, 1796, 8185, 12656, 15796, 35744
EMPR EXPL 1984-295; 1987-C260; 1996-C6; 1998-A1-A15
EMPR GEM 1969-171,173; 1970-204
EMPR INF CIRC 1992-1, pp. 5,6; 1993-1, p. 5
EMPR OF 1999-7
EMPR PF Cyprus Anvil (Cominco Ltd. (1967-01-10): Claims, Geology and Drill Holes Plan Map - Gibraltar; Gibraltar Mines Ltd. (1967-02-08): Location Map of Summit and Jan Groups - Showing Diamond Drill Holes 1-10; Cominco Ltd. (1967-12-15): Gibraltar Mines Property - McLeese Lake, Summary Report of Exploration (1967); Coast Silver Mines Ltd. (1968-01-12): Induced Polarization Survey Map - Summit Claims - Marguerite Area; Morocco Mines Ltd. (1969-01-01): Induced Polarization Survey - Chargeability Plan Map - Summit Claims - Marguerite Area - Plate 2; Morocco Mines Ltd. (1969-01-01): Claim Map - Summit and Bit Claims)
EMPR PF Rimfire (Sirola, W.M. (1963-04-25): Re: Try Group)
GSC MAP 12-1959; 1424A; 1538G
CIM Spec. Vol. 15, pp. 195-205; *46, pp. 201-213
GCNL #220, 1969; #153, 1991; #36(Feb.22), 1993
N MINER Oct. 5, 1992
(see 093B 012 for general references on Gibraltar Mine)
*Weymark, R. (2019-11-06): Technical Report on the Mineral Reserve Update at the Gibraltar Mine, British Columbia, Canada