This year,
“Last year, we learned that certainly not all the kimberlites had been discovered and that some of the microdiamond results obtained earlier [by De Beers] were not the best you could get off the property,” Diamonds North President Mark Kolebaba tells The Northern Miner. “We’re now seeing a much broader and more robust range of microdiamond results.”
The Blue Ice holdings cover 1,821 sq. km of staked claims, including the 20-km-long linear corridor, dubbed the Galaxy trend. A series of intermittent kimberlite dykes, blowouts and pipe-like bodies occur along this structural corridor, which has been defined by geophysical surveys and heavy mineral sampling. The Galaxy corridor straddles the Nunavut-Northwest Territories border; it is anchored by the Snow Bunting kimberlite on the eastern end of the Nunavut side and by the Snow Goose kimberlite at the western end on the Northwest Territories side.
The Snow Bunting, Snow Goose and Sandpiper kimberlites were discovered by
In 2002, Diamonds North targeted the the Nunavut section of the Galaxy trend, completing ground magnetic surveys and prospecting over a 9-km-long portion. “The eastern third of this structure is dominated by kimberlite dykes and blowouts,” says Kolebaba. “The [remaining] eastern two-thirds is maybe pipes and minor dykes.” Last year’s work was restricted to the Nunavut side because the Northwest Territories authorities were slow in granting permits.
On Victoria Island, the Archean granitic basement is overlain by a Proterozoic sedimentary sequence with minor volcanics, capped by flat-lying Cambrian-to-Devonian carbonate rocks. The host cover rocks are largely non-magnetic, and the kimberlite bodies stand out in the magnetic surveys as distinct “sharp” anomalies indicative of a shallow body, compared with the more “rounded” anomalies caused by deep features in the basement or within the sedimentary rocks. Kimberlite intrusions are associated with both positive and negative magnetic signatures. Rare thin volcanic beds in the limestones, as well as moraines with high concentrations of exotic magnetite, are the source of some the distinct anomalies.
The age of the kimberlite intrusions ranges from 256-257 million years to as old as 286 million years.
Topographically, the Victoria Island Arctic tundra terrain is flat to rolling and riddled with small lakes. The properties are accessible by light aircraft — a 1-hour flight from Cambridge Bay.
Drilling on the Blue Ice property in 2002 resulted in the discovery of three new kimberlite bodies, Vega, Virgo and Carina, and re-tested the Snow Bunting and Sandpiper. With the exception of the Snowy Owl pipe, all of De Beers’ discoveries have received only a small amount of work, limited to one or two short vertical holes.
Diamonds North drilled two angle holes into the Sandpiper kimberlite. The first, collared on the northern fringe of an elongated geophysical feature, intercepted 4.1 metres of kimberlite at a down-hole depth of 36.2-40.3 metres, followed by a second kimberlite intercept less than 1 metre thick. The second hole was drilled 75 metres away, near the centre of the body, and intersected 51.4 metres of uninterrupted kimberlite at a depth of 42.8-94.2 metres.
A 6.49-kg sample from the first hole returned a staggering 118 microdiamonds weighing 0.109 carat in total. The three largest stones recovered measure 2.19 by 1.51 by 0.85 mm, 1.94 by 1.31 by 0.69 mm, and 1.82 by 1.71 by 0.89 mm. “It’s encouraging,” says Kolebaba. “The sample has a high stone frequency and a flat curve that trends off well into the two-millimetre size.”
By comparison, a 76.84-kg sample from the second hole produced only 30 microdiamonds, with the largest stone measuring 1 by 0.6 by 0.34 mm. De Beers’ discovery hole into the Sandpiper was said by Kolebaba to have returned a low-to-modest microdiamond count.
The Sandpiper is believed to be a fissure, with a later small blowout or pipe cutting through that is less diamondiferous.
The Snow Bunting kimberlite, 1.5 km east of Sandpiper, was re-tested with a single angle hole, which confirmed the body to be 10 metres thick over a projected length of 200-250 metres. A 16.7-kg sample yielded 15 diamonds, four of which exceed 0.5 mm in two dimensions. De Beers originally recovered 23 stones from 137 kg of processed kimberlite.
The Carina discovery was made 7.5 km west of Sandpiper. With a ground magnetic signature measuring 200 by 150 metres, Carina was partially tested by three incomplete holes. An upper phase of clay-rich kimberlite, encountered between 44 and 62 metres of depth, was separated from a more competent, medium-to-coarse-grained lower phase by 8-10 metres of limestone. The lower phase delivered modest microdiamond results of 78 stones in 68.72 kg of sample, including one diamond exceeding 1 mm in two dimensions.
“Lower Carina is a slightly different kimberlite,” says Kolebaba. “It seems to be a little bit more of a peridotite source.” A 23.69-kg sample of the upper phase yielded eight diamonds.
Diamonds North pulled a 6.2-metre-long intercept of kimberlite from an angle hole drilled into the Vega discovery, 1 km west of Sandpiper. Twenty diamonds were recovered from a 22-kg sample, including one stone measuring greater than 0.5 mm in two dimensions.
Drill-testing of the Virgo target, lying between the Sandpiper and Snow Bunting, intersected three narrow kimberlite dykes ranging in thickness from 0.52 to 0.87 metres. The narrow dykes did not provide enough sample material for microdiamond analysis.
While conducting ground geophysical surveys last year, crews turned up three separate kimberlite float occurrences, Sculptor, Pegasus and Zeta, which were manually trenched.
Sculptor is a dark green, coarse-grained, olivine-rich kimberlite breccia exposed in float over a length of 250 metres. A 208.58-kg sample collected from several trench sites along a 350-metre section of the Galaxy structure returned 254 diamonds. The three largest stones measure 2.22 by 2.05 by 1.1 mm, 1.57 by 1.28 by 0.92 mm, and 1.57 by 1.54 by 0.68 mm. “Again, a nice distribution with upwards of two-millimetre size fractions,” explains Kolebaba. “This sample is definitely similar to AV-1, discovered by Stornoway and Northern Empire [on the Melville Peninsula]. The anomaly has a lot of potential for size and tonnage.” The Sculptor showing is 2.5 km west of Sandpiper.
Pegasus, 100 metres north of Sculptor, is a macroscopic olivine-rich kimberlite breccia. Bedrock was not reached in trenching, and only float material was sampled. A total of 336.54 kg of kimberlite was collected from two test pits, returning 52 diamonds, including one stone measuring 1 by 0.97 by 0.67 mm.
The Zeta showing is a dark, fine-grained hypabyssal kimberlite at least 0.4 metre wide in the bottom of a shallow test pit. Twenty diamonds were recovered from a 234.2-kg sample collected from a single exposure 4.5 km west of Sandpiper. One stone exceeded 0.5 mm in two dimensions.
High chrome
Kolebaba says the indicator mineral chemistry of the Victoria Island kimberlites shows both a good G10 signature, as well as a strong eclogitic signature. “The G10 signature is not like the Ekati signature,” he points out. “It doesn’t go quite as sub-calcic, but it’s
high chrome — much higher than what you see at Ekati.” The high chrome component suggests a promising geotherm of 38 mW per metre square. Indicator-mineral chemistry suggests components of both peridotitic and eclogitic mantle have been sampled by these kimberlites, with a more substantial credit coming from the eclogite.
This summer, crews will collect larger samples from the kimberlites that have good microdiamond counts (Carina, Sandpiper, Snow Bunting and Vega). It is anticipated that 2.5-3 tonnes of kimberlite will be recovered. An excavator may be brought in to take a larger surface sample from Sculptor. Diamonds North also plans to drill-test seven new targets, primarily on the Northwest Territories portion of the Galaxy structure in 2003, and re-test the Snow Goose kimberlite, which De Beers discovered in 1999. Snow Goose has a 50-metre-diameter circular magnetic low signature and an adjoining southeasterly oriented anomaly, which Kolebaba suspects is a dyke. De Beers recovered 55 diamonds from 151 kg of kimberlite sample, including a 0.23-carat stone.
In addition, an extensive airborne geophysical survey will be completed over the project area (only 25% of the project has been covered to date by airborne).
On completion of the 2003 program, Teck will have the option of earning an initial 30% interest in the Blue Ice claims by exercising $500,000 of Diamonds North warrants and by spending $9.5 million on exploration over three years. 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%. Teck can earn an additional 5% by arranging project financing.
Farm-out
The business strategy of the company is to reduce its financial risk by farming-out its projects so that it can have more “irons in the fire.” Kolebaba says Teck is able to spend faster and better than Diamonds North. “Teck is a good bet for us because they are quite keen on growing their company,” Kolebaba says. “and it will be diamonds that will help them grow.” Teck already has a joint-venture arrangement in place with
Diamonds North controls virtually the entire diamond district on Victoria Island.
Covering portions of both Nunavut and the Northwest Territories, 700 km north of Yellowknife, Victoria Island was recognized for its diamond potential by Diamonds North’s predecessor, Major General Resources, back in 1993. The premise that portions of Victoria Island were underlain by an Archean basement, representing the northern end of the Slave Craton, was supported by outcropping granitic rocks east of the project area, which were age-dated in 1996 at 2.6 billion years.
When
Five of the Mon claims lie in the Blue Ice project, 16 are on the wholly owned Hadley Bay project, and one is on the Holman project, a 50-50 joint venture with
Spinoffs
Major General completed a re-organization in early 2002, spinning off its diamond assets into the newly created Diamonds North, while rolling back its owns shares on a 3-for-1 basis. In the process, Major General was re-named
Diamonds North has 19.2 million shares outstanding, or 25.5 million on a fully diluted basis, with $3.2 million in cash. The company is trading around 75 in a 52-week range of 95-31.
Diamonds North holds more than 6,070 sq. km on Victoria Island. Separate projects have been optioned to
Majescor can earn a half-stake in the 1,176-sq.-km Wellington project, immediately east of Blue Ice, by spending $2.2 million over three years. Last fall, Diamonds North flew a helicopter-borne magnetic survey over 16 isolated geophysical targets, further defining six “nice pipe-like anomalies” and three potential kimberlite dyke anomalies. This summer, three of the anomalies were drilled without intersecting any kimberlite. Further work this summer will include additional till sampling and manual trenching on a known kimberlite dyke.
Elsewhere on Victoria Island, Diamonds North and Majescor are jointly exploring a small parcel of permits up north on Stefansson Island. These claims were acquired last year to cover “a discrete indicator mineral anomaly.”
Holman
The Holman project, covering 516 sq. km west of Blue Ice, is under option to Serengeti, which can earn a half-interest by spending $2.1 million over three years. Two discrete anomalies will be drill-tested this summer. In addition, a series of helicopter-borne magnetic surveys will be flown over 24 anomalous targets.
Canabrava spent a little more than $1 million re-testing the diamond-bearing King Eider and Turnstone kimberlites. Airborne geophysics flown last fall revealed a 10-km-long structural corridor of kimberlite, much like the Galaxy structure, along trend of King Eider.
Hawkeye Gold recently converted an option to earn up to a 50% interest in the 122-sq.-km Yankee property to a 10% interest.
Diamonds North and its joint-venture partners are budgeted to spend about $4.6 million on diamond exploration in 2003, including $300,000 on six regional grassroots programs across Canada.
In the southern Slave region, Diamonds North holds a 24% interest in the Misty Lake project and a 40% stake in the Kidme claims, just south of the Kennady Lake project. Both projects are held in partnership with
BLUE ICE MICRODIAMOND RESULTS
| Sand | |||||||||
| Snow | Piper | Sand | Upper | Lower | |||||
| Bunting | East | Piper | Vega | Pegasus | Sculptor | Zeta | Carina | Carina | |
| Sieve Size | #Diam | #Diam | #Diam | #Diam | #Diam | #Diam | #Diam | #Diam | #Diam |
| +1.180 mm | 0 | 2 | 0 | 0 | 0 | 2 | 0 | 0 | 0 |
| +0.850 mm | 0 | 3 | 0 | 0 | 0 | 2 | 0 | 0 | 0 |
| +0.600 mm | 0 | 3 | 0 | 0 | 1 | 9 | 1 | 0 | 2 |
| +0.425 mm | 3 | 8 | 1 | 0 | 2 | 21 | 0 | 1 | 0 |
| +0.300 mm | 1 | 15 | 3< /td> | 3 | 3 | 33 | 1 | 2 | 5 |
| +0.212 mm | 4 | 25 | 6 | 5 | 7 | 48 | 4 | 1 | 15 |
| +0.150 mm | 3 | 35 | 7 | 6 | 16 | 69 | 5 | 3 | 23 |
| +0.100 mm | 4 | 27 | 13 | 6 | 23 | 70 | 9 | 1 | 33 |
| Total Diamonds | 15 | 118 | 30 | 20 | 52 | 254 | 20 | 8 | 78 |
| Sample Wt(kg) | 16.7 | 6.49 | 76.84 | 22 | 336.54 | 208.58 | 234.24 | 23.69 | 68.72 |
| Galaxy Trend | |||||||||
| Location (Km) | 1 | 2.4 | 2.5 | 3.5 | 4.7 | 5 | 6.5 | 10 | 10 |
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