Atlantic Report Tin operation back on track

The East Anglia Kemptville, N.S., tin mine is back on track, with improved recoveries and a daily milling capacity greater than originally planned, according to manager Ken W. Collison of the Rio Kemptville Tin Corp.

Reporting recently on the status of the operation to the Halifax branch of the Mining Society of Nova Scotia, Collison reviewed the history of the deposit since 1979, when 1987 PDA Prospector of the Year, Mert Stewart, discovered tin- bearing float in the Plymouth area of Yarmouth Cty., about 45 km southwest of the eventual mine site. On the basis of this discovery, Shell Minerals became interested in the region and, using geophysics and till geochemistry, found the East Kemptville tin deposit.

When Shell decided to sell the deposit in 1983, Rio Algom (TSE) was the successful bidder. The first ore was put through the mill late in 1985. That October, the price of tin was about $9 per lb, but by start-up in November, the tin price had fallen by two-thirds. By the end of 1986, it was apparent to the company that cash flow from the mine would be insufficient to pay the $140 million debt that had accumulated. Rio Algom exercised one of the terms in the banking agreement and turned the operation over to the banks in December, 1986.

The banks formed the East Kemptville Tin Corp. and decided to operate the mine and improve recoveries, hoping that the price of tin would recover and the mine could be sold for a better price.

Last summer, the banks put the deposit up for sale and Rio Algom once again was the successful bidder. Rio Algom executives expect tin to be around $3.50(US) for the rest of this year, a price that suits the company’s competitive position.

The mine’s tin recovery process is complex, using several gravity and flotation methods. Initial recoveries of 40% were much lower than the 75% expected, due to the nature of the cassiterite. In ore tests, the cassiterite occurred as fairly large resilient grains amenable to traditional gravity separation. Subsequent work has shown that the cassiterite is stressed and pulverizes into a large percentage of finer grains in the rod mills. The mill circuit has been modified and recoveries are now about 65%, the maximum the present mill configuration is capable of producing. To retrieve this fine-grained tin, the company has been researching the use of flotation methods for recovering cassiterite.

Rio Algom officials have visited East Germany and Tasmania, where this technology is being used successfully. It is expected that a flotation circuit could increase tin recoveries to about 75%.

Byproducts of the mine include topaz and a copper-silver concentrate. The concentrate contains 300 grams per tonne silver and the mine produces 200 tonnes of copper- silver concentrate per month.

Reserves consist of 40 million tonnes of “high grade,” averaging 0.185% tin, and 15 million tonnes grading 0.105% tin. At a planned production rate of 3.4 million tonnes per year, the mine has a life of 13 years, with 17 years for the mill. There is potential for adding to the reserves at depth, Collison says. The mill is now operating at a rate of 9,400 tons per day at an average grade of 0.165% tin and a recovery rate of 65%. The mill has state-of-the-art equipment to monitor the mill circuits. As things happen relatively quickly in the mill, an efficient monitoring system is required. Within 30 minutes from when ore enters the rod mills, the tin is either in the finished concentrate bin or in the tailings area.

Rio Algom has used mostly local labor at East Kemptville and has spent over $3 million on job training. This investment has paid off with a productive, stable and dependable workforce. Operating costs of $2.5 million a month include $850,000 for labor and $250,000 for power.

Nova Scotia produces 3% of the world’s supply of tin. The East Kemptville mine is the fifth-or sixth single-largest source of the metal.

The Canadian Save Flow- Through Committee visited Halifax recently on its cross-Canada tour, hosting a day-long seminar. Speakers included representatives of the mining industry, various levels of provincial government, and rural Nova Scotia communities which have benefited from funds made available by the flow-through tax incentive.

Flow-through shares have created the boom in the Nova Scotia mining industry over the last four years. They were responsible for $100 million in capital investment in the province in 1987.

“It’s one of the best job-creation programs the federal government has ever implemented,” said Greg Isenor of Seabright Resources, who helped organize the seminar.

Other speakers noted that real regional development has come from the use of flow-through shares, and that flow-through shares finance about 70% of mineral exploration in Canada, most of it in remote regions.

The wardens of Halifax and Guysborough cties. were enthusiastic about flow-through shares, saying they’ve observed substantial drops in social assistance costs in their areas with the employment of local residents by Seabright Resources (TSE) and Coxheath Gold Holdings (ASE). Groceries, residential developers, hardware and furniture stores, gas stations, restaurants and motels, home rentals and drilling companies have all experienced increases in business due to flow-through funding, the wardens said.

“Flow-through has been very important to my business and to my clients,” said Rob Peters, chairman of the Investment Dealers Association Atlantic District Council. “More major gold mines have been found since 1980 than in all of Canada’s previous mining history,” he said, attributing that fact to the use of flow-through shares.

Nova Scotia mining company representatives, including Dr Jack Garnett of Seabright, Craig Miller of Scotia Prime Resources, Gerald McConnell of NovaGold Resources and Jim Breeze of Coxheath, described how their companies have benefited from flow-through shares.

Flow-through shares result in money being invested in the economies of regions of high unemployment, and the rural areas of the province where government programs have failed to create stable economic development, other speakers noted.

Some speakers at the seminar pointed out that because of the multiplier effect in the economy, the government gets back most of its lost tax revenue through increased levels of employment, corporate profits and taxes on consumption.

Governments also save on social services and unemployment costs. A storekeeper from the Musquodoboit Valley summarized the general feeling at the seminar by saying, “Flow-through shares have been the best thing any government has done for my business.”

A gold symposium co-sponsored by the New Brunswick Department of Natural Resources and the New Brunswick PDA will be held in Saint John from June 8-11. Talks will cover gold deposits and occurrences in New Brunswick and their relationship to tectonic evolution.

A field trip will take participants to New Brunswick’s primary gold producer, the Cape Spencer open pit mine where gold is associated with a major thrust fault zone, and to other prominent gold occurrences in the province, the Alcida and Upsalquitch areas, where gold is related to mafic and intermediate dikes in strike-slip fault zones.

For more information, contact Dr A. A. Ruitenberg at the N.B. Dept. of Natural Resources in Sussex, telephone (506) 433-4317.