Diamond fever at Kirkland Lake

Some of the limelight focused on the Lac de Gras diamond play is finding its way back to Kirkland Lake, Ont., home of the first kimberlite discovery in Canada.

Since that initial find in 1968, at least a dozen kimberlite pipes and dykes and a handful of diamonds have turned up near Kirkland Lake. But despite sporadic interest from some seniors, including Lac Minerals (TSE) and De Beers subsidiary Monopros, there has never been a major exploration drive for diamonds in the area.

Land availability is one of the main obstacles. In contrast to the Lac de Gras area of the Northwest Territories, where stakers have been able to claim about 10,000 square miles of open ground, most of the land along the Kirkland Lake break is reserved for gold exploration. For diamond mining hopefuls who require large tracts of ground for effective exploration, options and property acquisitions in the area are expensive and time-consuming. But according to Keith Barron, a Ph.D. student at the University of Western Ontario, the potential for finding economic kimberlites around the historic gold mining town is too great to ignore. He says the younger breaks that intersect the Porcupine-Destor fault zone at right angles provide the ideal “zones of weakness” favored by kimberlite intrusions.

His argument is supported by the configuration of the pipes found to date. A glance at the Ontario Geological Survey’s Bedrock Geology of Ontario map shows that the known pipes line up from Gauthier Twp. to Michaud Twp. in a distinct north-northwesterly direction.

Barron adds that an ignorance of kimberlite geology in Canada has probably led to incorrect identification of many of the pipes in the area. “We should haul out some of the old core and some of the old sections and take a second look at what was logged as peridotite or diabase,” he told geologists gathered recently for the Mines and Minerals Symposium in Timmins, Ont.

Later, in an interview with The Northern Miner, Barron said a widespread overburden sampling program for indicator minerals would help pinpoint the kimberlites that have no magnetic signature. On average, about one third of the world’s known kimberlites do not respond to magnetics, he said. Earlier this year, Sudbury Contact Mines (TSE) touched off a modest staking rush when it announced the discovery of eight microdiamonds (less than 0.45 millimetres in diameter) in a pipe just west of Larder Lake (T.N.M., Apr. 6/92). With the financial backing of Agnico-Eagle Mines (TSE), Sudbury Contact is planning to resume drilling this summer.

More recently, Gwen Resources (ASE) announced the discovery of a kimberlite pipe on the side wall of its New Buffonta open pit in the Harker-Holloway camp. Gwen says the pipe has been exposed to a depth of 90 ft. and is looking for a partner to conduct further exploration.

In Eby Twp., Greater Lenora Resources (TSE) says it has identified kimberlite indicator minerals, including chrome diopside and pyrope garnets, in samples collected during a 1987 reverse circulation drilling program. Lenora intends to investigate some of the magnetic highs on its property by trenching and drilling.

Wheaton River Minerals (TSE) says it has an option to earn a 50% interest in five groups of claims in the Kirkland Lake area which the company says have the potential to host kimberlite pipes. Joint owners of the property are Wheaton’s parent, Glencairn Explorations, and Strike Minerals. But the only pipe in Central Canada that has yielded diamonds larger than one millimetre is the C-14 pipe in Clifford Twp. Now owned by Regal Goldfields (CDN), the C-14 has had a colorful history.

In 1989, Lac Minerals (TSE) decided to sell its diamond properties, including the C-14 pipe (where it found eight macrodiamonds) to Dia Met Minerals (VSE). Dia Met is the key participant in the Northwest Territories diamond play. In a September, 1990, article for the Canadian Mining Journal, Dia Met’s Charles Fipke had this to say about the Kirkland Lake holdings: “(The) C-14 kimberlite property . . . should produce diamond grades of about equivalent to the Premier diamond mine, South Africa (about 30 carats/ton). . . . the favorable indicator mineral plots correlate well with diamonds recovered to date and are significantly more favorable than plots from other North American kimberlites of sub-economic grades.”

Not long after the article was written, however, Dia Met forfeited its right to the property by failing to renew its Ontario prospector’s license. Regal noticed the open ground during a casual visit to the mining recorder’s office and quickly staked over it, said Regal President Douglas Bannerman. A subsequent claim dispute lead to an out-of-court settlement in April, 1991. In return for 100% interest in 64 claims, including four known kimberlite pipes, Regal paid Dia Met $100,000. Dia Met retains a 2.5% royalty on the claims.

Through a public offering of 500,000 flow-through shares at $2, Regal is trying to raise enough money to run a ramp into the 5-acre C-14 pipe and extract a 5,000-ton bulk sample. Meanwhile, the company has acquired two more properties in Morrisette, Gauthier and McElroy twps. and is bidding for a third.

“We’ve only just scratched the surface in this area,” says Barron. “I think we’re going to come up with the first diamond mine in Ontario.”