Diamonds North leads juniors in exploration
It’s been 14 years since Chuck Fipke made the historic Point Lake diamond discovery in the Lac de Gras Arctic region of the Northwest Territories, spawning one of Canada’s greatest staking rushes of all time. The rewards have been unparalleled, with subsequent discoveries resulting in two world-class diamond mines, Ekati and Diavik, and a third much smaller mining operation — Jericho — set to come on-stream early in the new year.
In terms of value, Canada leaped ahead of South Africa in 2004 to become the world’s third-largest diamond producer behind Botswana and Russia. This year,
Although there are fewer players today, the search for Earth’s most precious gem continues unabated as companies expand their sights to all corners of Canada’s Far North. Leading the charge are De Beers and
By conducting an aggressive northern reconnaissance exploration initiative, Diamonds North acquired nearly 52,609 sq. km of new prospective permits across the Far North earlier this year, bringing its land holdings to a staggering 109,265 sq. km. The package of new permits issued to Diamonds North at the beginning of February was second only to the package issued De Beers, which acquired 98,338 sq. km of new prospecting permits in Nunavut and 18,615 sq. km in the Northwest Territories. BHP Billiton was third on the list, with 32,779 sq. km of newly acquired holdings.
“The new permits represent a prospective landholding that positions the company in many under-explored terrains with indicated diamond potential,” Diamonds North President Mark Kolebaba said at the time.
Led by Kolebaba — formerly with BHP Billiton’s diamond exploration division — Diamonds North has attracted some of the world’s major mining companies as partners, including
Teck Cominco has taken an aggressive approach at Victoria Island by spending upwards of $4 million this year. Under a 2003 option agreement, Teck can earn up to a 70% interest in the Blue Ice project, which has been amended to include the Hadley Bay and White Ice properties. As the operator, Teck can earn an initial 30% stake by spending $11.5 million on exploration by the end of 2006. Teck can then elect to increase its interest to 50% by incurring an additional $5 million over one year. Should Teck continue funding all exploration costs to the completion of a feasibility study, the major would boost its stake to 65%, or ultimately 70%, by arranging project financing.
The Victoria Island kimberlites occur mainly as a series of en echelon dykes and blows, as well as a number of pipes, along four distinct structural or linear trends — Galaxy, King Eider, Apollo and Snowy Owl — all running northwest-southeast.
The Blue Ice holdings cover the Galaxy kimberlite trend, a 20-km-long corridor that straddles the Northwest Territories-Nunavut border and hosts 14 kimberlite occurrences. A second parallel magnetic trend of kimberlite bodies and showings is centred on the King Eider pipe, 30 km north of the Hadley Bay project. The King Eider trend is more than 25 km long and hosts eight kimberlites.
Teck kicked off this year’s program by testing more than 70 targets with a mobile reverse circulation (RC) drill rig. Kolebaba acknowledges that a lot of the targets were high-risk. The second part of the program concentrated on King Eider, which has demonstrated potential for large-carat stones. In last year’s drilling, a 0.75 carat diamond, measuring 5.5mm in its longest dimension, was found among a 1.32-carat parcel of diamonds recovered from a composite 679-kg sample. The sample was collected from four holes in the central portion of the pipe-like body.
The actual weight of the diamonds exceeding 0.85 mm — 10 diamonds in total — is 1.09 carats, equal to a sample grade of 1.6 carats per tonne.
“The big driver for the project going forward is King Eider,” Kolebaba says.
This year, Teck collected more than 3 tonnes of sample from King Eider through additional core drilling. Defined by a distinct magnetic anomaly measuring 300 by 200-metres, the exact size of King Eider has not been determined, though Kolebaba says it stands up pretty well to a project like Jericho, which hosts a kimberlite resource of 7.1 million tonnes.
Some of this year’s budget went to till sampling and airborne geophysics on parts of the project that had never been previously sampled or flown.
“The focus has been to try to find another big body; we haven’t really looked at it from a small mine point of view, which is starting to look interesting from the King Eider point of view,” explains Kolebaba.
Kugaaruk joint venture
Last year, Diamonds North merged its Amaruk project with the Pelly Bay area holdings of BHP Billiton to create a 50/50 joint venture covering a 35,000-sq.-km area near the community of Kugaaruk in eastern Nunavut. Under the arrangement, BHP Billiton is the project operator and can earn an extra 10% interest by incurring all exploration costs up to the completion of a feasibility study within seven years. BHP will have the right to earn a final 65% by arranging all financing to production.
This past summer, as part of a $3.5-million program, BHP collected another 2,300 till samples from the project area as a follow-up to the 3,200 samples taken in 2004. An additional 12,000 line-km of helicopter-borne magnetic and electromagnetic geophysical surveys was also flown, adding to the 11,000 line-km completed last year.
The project area was systematically sampled on anywhere from a 4 by 5-km grid down to a 1 by 2-km grid in 2004. A number of these tills were highly anomalous in kimberlite indicator minerals, returning in the thousands of mineral grains from 10-15 kg samples. Three of the best till samples each held over 4,000 indicator mineral grains, ranging from 4,148 to 4,736 individual grains.
“The garnets are showing nice high-chromium, low-calcium G10 chemistry,” Kolebaba remarks.
During a brief, 2-day visit to the project by Kolebaba at the end of last year’s field season, kimberlite boulders and fragments were found in three separate areas. In one area, boulders of kimberlite were found at five discrete sites, forming a 2.3-km-long corridor. A 287-kg sample taken from the boulders contained seven small microdiamonds no bigger than a 0.212-mm sieve-size.
Prospecting in 2005 around selected till sample sites identified what Diamonds North believes is between 15 and 18 discrete kimberlite boulder occurrences across a span of 62 km. Kolebaba defines an occurrence as something that could be potentially sourced from one individual body; one occurrence could contain as many as 150 boulders, he explains.
Samples weighing between 25 and 100 kg were collected from five of the kimberlite occurrences for microdiamond analysis, while samples from nine of the occurrences are being analyzed separately for indicator minerals.
The summer work also resulted in the discovery of the Umingmak kimberlite, the first confirmed in situ kimberlite in the region. Umingmak is exposed in three outcrop showings within a topographically low, overburden-covered area. Umingmak has the potential to be a 200-metre-
wide body, Kolebaba says.
Umingmak is described as an olivine-rich macrocrystic kimberlite, with lots of visible chrome diopsides and purple-coloured garnet, plus ilmenite. Two samples totalling 500 kg have been submitted for microdiamond analysis.
In addition, Umingmak provides the joint venture with a confirmed geophysical signature in the airborne data.
“It serves to corroborate the geophysics,” Kolebaba says. “We have other (geophysical) targets, even in this small area, that look very similar.”
Kolebaba adds: “The Amaruk project has been methodically and rapidly advanced from a massive land position with good diamond indicators to a drill-ready project with multiple kimberlite occurrences — providing plenty of blue sky in a relatively short period of time.”
Ultimate indicator mineral
Elsewhere in the immediate area,
The Barrow project is 15 km south of Kugaaruk and covers 445 sq. km. Some of the indicator minerals recovered from last year’s till samples were shown to have diamond inclusion chemistry, including several high-chrome G10 pyrope garnets. During the course of the 2005 summer program, diamond-bearing kimberlite float was discovered in the vicinity of one of the high-priority airborne targets. A single microdiamond measuring 0.55 by 0.42 mm in its two longest dimensions was recovered during the indicator mineral analysis of a 6.7-kg sample of the kimberlite, which is described as a medium to coarse-grained macrocrystic hypabyssal phase.
“The fact that a diamond was recovered during the process for extracting the far more abundant suite of indicator minerals is remarkable,” says Bruce Counts, president of Indicator Minerals. “Diamond is the ultimate indicator mineral and its presence in this small sample reaffirms our belief that this may be a significant new diamond district.”
Follow-up field work on the 800-sq.-km Darby project, 120 km southwest of the hamlet of Kugaaruk, resulted in the discovery of three distinct kimberlite float occurrences. Last year’s till sampling confirmed the presence of kimberlite indicator minerals, some of which exhibit promising diamond inclusion chemistry, including high-chrome G10s.
The Barrow and Darby projects are part of a 28,327-sq.-km package of prospecting permits and mineral claims in eastern Nunavut, in which Indicator has the right to acquire an 80% interest from the privately led staking syndicate Hunter Exploration Group. This package also includes the Baumann project, which comprises some 11,331 sq. km of newly acquired prospecting permits on Ellesmere Island that have been optioned to Stornoway Diamond. The Ellesmere Island permits were acquired based on regional heavy mineral sampling by the Hunter Group, which confirmed the presence of kimberlite indicator minerals, including a lone G10 garnet with high-chrome composition.
By spending $1 million before the end of 2009, Stornoway, acting as operator, can earn 41% of the Ellesmere Island project, leaving Indicator with 39% and the Hunter Group with 20%.
Other junior companies active in the Kugaaruk hamlet area include
During 2004, Trigon completed a reconnaissance till sampling program across the IC and CO properties over a total project area covering 3,196 sq. km. Pyrope garnets and chromites were recovered at several sample sites on the IC claims, including G10 garnets and one pyrope grain with a kelyphitic rim, suggesting the mineral grain had not travelled far. An anomalous concentration of kimberlite indicator minerals was identified at the centre of the IC block.
A 2005 program of airborne geophysics, till sampling and prospecting was aimed at further defining the potential source of the anomalous tills. A 5,200-line-km airborne survey was flown over the IC claims, followed by the collection of 226 till samples.
Trigon also took 37 regional till samples from the adjoining TIM property, which covers 321 sq. km and is held under a joint-venture arrangement with
Diamonds North also joined forces with
In 2004, Kennecott completed 20,000 line-km of airborne magnetic surveys over the project and collected 223 heavy mineral samples, recovering a full suite of kimberlite indicator minerals. After further defining 20 of the more promising airborne anomalies with detailed ground geophysics, Kennecott drill-tested seven targets this past summer.
Regional initiatives
Diamonds North regional exploration initiatives have led to the identification and permitting of more than 10 new project areas. One of these is on the northeastern side of Banks Island in the High Arctic, comprising 4,850 sq. km of permits. A 50/50 joint venture, the Banks Island project was formed in 2003 with
Two main drainages were isolated and further sampled in 2005.
“We’re getting good indicators, the right kind of textures on the indicators for proximity and good chemistry,” Kolebaba says.
The big push this year for Diamonds North was at Hepburn, which covers 14,500 sq. km of permits and claims in the Northwest Territories, 300 km north of Yellowknife on the western margin of the Slave. The project area covers one of the last remaining regions of the Slave craton that is relatively unexplored for diamonds.
“It was one of the only areas in the Slave that has never been staked,” Kolebaba explains.
Regional samples from the project area revealed kimberlite indicator minerals including pyrope and eclogitic garnet, chrome diopside, olivine and chromite. Diamonds North is confident that these indicator minerals originate from a source in the project area. The earlier sampling revealed a distinct up-ice cutoff, which, according to the company, means the grains were not glacially transported from the nearest-known kimberlites in the Lac de Gras camp, 100 km to the east. In addition, primary surface textures on some of the recovered mineral grains, including fragile kelyphite rims on garnet, indicate a nearby source.
The project area was sampled in great detail this summer, with about 1,000 till samples taken. The goal is to isolate an area for airborne geophysical surveys.
The junior also completed further detailed sampling on the Tasiq project, which is completely enclosed by a large
property block held by De Beers, south of Baker Lake in Nunavut. De Beers acquired 16,187 sq. km of permits in early 2004 but was forced to leave a large gap open in the centre of this block due to a small pre-existing gold claim.
Diamonds North recognized that the open ground in this block was probably left open because of permit regulations and not for geological reasons. A sampling crew was quickly mobilized to the area and based on positive findings, Diamonds North staked the 1,800 sq. km of open ground.
Till samples from the Tasiq project yielded an assortment of pyrope garnet, chrome diopsides and an ilmenite, with a possible remnant of kimberlite attached. One sample returned more than 70 mineral grains.
“We know the ice direction and there are no grains going into the block but there are grains coming out of the block,” Kolebaba says. “We are assuming we have a cluster of kimberlites in that block.”
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