Here's something to read while we wait for Labrador:
(from International Wayside's website on the Cariboo, a little off topic):
The Cariboo Gold District has been a world class producer of gold, and was the cause of the Cariboo Gold Rush in 1865. The district was a prolific producer of both placer gold and, since the 1930's, was considered primarily a hard rock gold mining area.
The CGQ Mine, IM Mine and the MCG Mine produced a total of 1.23 million ounces of gold, since 1933. Production was from a mineralized trend developed underground over a strike length of 3.5 miles, with a vertical range of 2000 feet, and a width of about 500 feet. Unexplored gaps exist within the plane of the developed trend. Two types of lode gold ore were mined in the Wells Region. 75% of the gold was recovered from crosscutting the quartz veins, producing ore with an average grade of 0.38 ounces gold per ton. The balance was from Replacement Ore with an average grade of 0.63 ounces gold per ton.
B.C. Mineral Statistics Annual Summary Tables estimate placer gold production for the Cariboo District amounted to 2,622,400 ounces to year-end 1985. Total production was probably closer to 3 million ounces of gold, since between the discovery of placer gold in the Stanley-Wells-Barkerville gold fields in the 1860's and, prior to 1874, gold production was unrecorded. The first indications of sustainable hard rock mining in the Wells area were not realized until the 1920's, when A.E. Sanders located the Rainbow Claims. Fred Wells purchased the Rainbow Group of Claims from A.E. Sanders and incorporated the Cariboo Gold Quartz Company ("C.G.Q. Company") in 1927. An adit was driven (1100 Level) in 1927, from an elevation of 4,375 ft. to intersect the quartz veins on the Rainbow Claims. These gold bearing quartz veins laid the basis for a mining operation at 50-60 TPD in 1933, increased to 100 TPD in 1935. Peak production of 350 TPD was reached in 1941. (40,000 ounces of gold annually).
During the period 1933 to 1959, the CGQ Mine produced 626,755 oz. of gold and 56,092 oz. of silver from 1,681,951 tons of quartz vein ore. A grade of 0.4 oz. gold per ton was required to meet pre-war production costs; this grade requirement had increased to 0.5 oz. gold per ton to meet production costs at the time of closure, Such a high grade was required because of the fixed gold price of US$35.00 until 1971.
The CGQ Mine consists of 36 miles of underground development on 13 levels (900 to 2100 Levels), between elevations of about 4,800 and 3,350 feet. The 1500 Level main haulage extends 10,500 feet to the B,C. Shaft on the B.C. Vein. Inclined raises from the 1500 Level and adits on the 1200 Level (4,300 feet), and 1000 Level (4,500 feet), provided access to upper Levels of the mine. Three shafts sunk internally from the 1500 Level to access the lower levels, these being the No. l Shaft in the No. 1 Zone, No.2 Shaft in the Rainbow Zone, and the No. 3 Shaft in the Sanders Zone. By the late 1940's, all the mineralized zones were interconnected by underground workings.
In 1940-41, the main haulage-way was extended 5,500 feet to the B.C. Vein, at the southeast boundary of the Property. No exploration or development work was reported as being carried out on this drift extension. The drift extension was wide, ranging from 20-42 feet in width. This B.C. vein will be further explored in 1996 and 1997.
In October 1942, gold mining was classified as a non-war industry by the Federal Government of Canada, which meant gold mines received no priority for labor or supplies. As a result, gold mines in British Columbia were unable to hire replacement labor for the duration of the war, or obtain necessary mining supplies, consequently the mining operation lost viability and never recovered from the 50% decrease in production levels. The CGQ Company could not sustain the required level of exploration drilling or proper underground development work, and the blocked out reserves were depleted and not replaced. In 1944, the first Replacement Ore in the CGQ mine was found, by accident, in the Rainbow Zone.
Post-war development was concentrated in the No. 1, and The Tailings Zones, below the 1500 Level through the No. 1 Shaft, in the Rainbow Zone through the No. 2 Shaft and the No. 1 - No. 2 Shaft connection. Similarly development work was conducted on the Sanders Zone through the No. 3 Shaft, and also on the Pinkerton Zone. In 1948 the No. 1 Shaft was deepened to the 2100 Level and gold bearing quartz ore was mined by selective stoping. A major Replacement Ore body, grading 0.70 ounces of gold per ton, was discovered in the Tailings Zone in 1950.
The CGQ Company purchased the adjacent IM Mine from Newmont Mining Corporation in 1954, and subsequently concentrated on the development of the higher value' gold Replacement Ore prevalent in the IM Mine. The Replacement Ore grading 0.6 oz./ton gold, dictated that the CGQ Company should redirect more of its resources towards development of the IM Mine, to the extent that by 1959, it was decided that production would only ensue from the IM Mine and mining at he CGQ Mine was discontinued. Of note is the fact that ore grades of 0.402 oz. per ton from quartz ore, and 0.699 oz. per ton for Replacement Ore, were still being mined at the time of closure of CGQ Mine in 1959. Reserves were reported at the time of closure 115,010 tons, composed of 1952 reserve write down of 46,600 tons of 0.27 ounces gold per ton, for a contained 12,582 ounces of gold, and 68,41 0 tons at 0.37 ounces gold per ton equaling 25,311.7 ounces of gold.
In the 1957 CGQ Company Annual Report, E.E. Mason, P. Eng., stated: "Figures include certain quantities also representing the six ore zones lying east of No. 1 Shaft, a distance of roughly 10,000 feet to the B.C. Shaft. They are not being worked, nor is any consideration being given to working them in the immediate future.
These are nominal quantities, not necessarily representative of the production possibilities of these zones. Rather can they be expected to resemble in productivity the three ore zones that have largely supplied the production of the last ten years and earlier. Ore grades and the major distances separating these from the active ore zones, however, render their development and exploitation impractical until an improved climate for gold production has evolved."
It is clear from CGQ Company Annual Reports at the time, that the decision to close the CGQ Mine was not based on a lack of reserves in the CGQ Mine, but was based on the concentration of effort mining Replacement Ore in the ]M Mine. A higher average mined grade of ore of 0.5182 oz./ton was being mined from the adjacent IM Mine, which the CGQ Company acquired prior to closure of the CGQ Mine. This mineable grade was obviously more attractive when compared with the 0.402 oz./ton obtainable at the CGQ Mine.
In the 1960 CGQ Company Annual Report, E,E. Mason stated, "The CGQ Mine closed because of exhaustion of ore structures developed in the Tailings and No. 1 Zone. Development of new ore reserves within this region would require the deepening of the No. 1 Shaft and 2000 feet of lateral development on each level". CGQ Company was not able to build cash reserves capable of financing such an undertaking, although it continued operations at the IM Mine until 1967.
1966 Dolmage-Campbell, Mining Consultants reported, "There is no doubt in the writer's mind that the CGQ Mine has outstanding potential for exploration for Replacement Ore bodies. From the information available there is no reason not to expect as much Replacement Ore in the developed parts of CGQ Mine as have been mined from Island Mountain to date, namely about 500,000 tons; with untapped potential at depth". |
