The first batch of drill results from the Sand Piper kimberlite body is providing early encouragement for
While conducting a summer program of exploration drilling on its wholly owned Blue Ice property, Diamonds North retested the Sand Piper kimberlite with two angle holes. The first, collared on the northern fringe of the elongated geophysical feature, intersected 4.1 metres of kimberlite at a depth of 36.2-40.3 metres. A second kimberlite intercept, measuring less than 1 metre thick, was cut by the hole. The second hole was drilled 75 metres away, near the centre of the body, and intersected 51.4 metres of essentially uninterrupted kimberlite between 42.8 and 94.2 metres of depth. Both holes were drilled at an angle of minus 60.
A 6.49-kg sample, representative of the 4.1-metre kimberlite intercept in the first hole, returned an impressive 75 microdiamonds and 43 macrodiamonds weighing 0.109 carat in total. A macro is here defined as exceeding 0.5 mm in at least one dimension. Eleven of the macros measure greater than 0.5 mm but less than 1 mm in two dimensions, whereas another seven diamonds exceed 1 mm in two dimensions. 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.
“This is an exciting result, as it combines high diamond counts with a large number of one-millimetre-plus stones in such a small sample,” states Diamonds North President Mark Kolebaba.
Partial results for the second hole include a 31.74-kg sample collected from the top 20 metres of the kimberlite intercept, which yielded 13 micros and four macros weighing a total of 0.002 carat. Microdiamond results are pending for the lower 30-metre kimberlite portion of the intercept. All kimberlite samples are derived from split BTW-size core (4.15 cm diameter). Diamonds North is saving half the core for future reference.
The geophysical signature of Sand Piper is a magnetic-low, measuring roughly 150 metres long by 80-100 metres wide.
“Geophysically, it looks like it’s a blow on what I would call a significant dyke structure,” says Kolebaba.
The kimberlite body appears to be sub-vertical based on the limited drilling.
Sand Piper is one of 16 kimberlite bodies discovered by De Beers on Victoria Island in the late 1990s. Kolebaba says De Beers encountered low-to-modest microdiamond counts in the Sand Piper kimberlite, with no macros. De Beers drilled one vertical hole into the thickest part of the body. He adds that Diamonds North’s own angled drilling shows quite a bit of variability in the stratigraphy of the kimberlite.
“It’s quite a complex system,” he tells The Northern Miner. “We don’t know what De Beers sampled in that one vertical hole; it might have been one or two phases.”
The Sand Piper kimberlite occurs near the southeastern end of a 20-km-long corridor Diamonds North calls the “Galaxy Trend.” A series of intermittent kimberlite dykes and small pipe-like bodies occurs along this (apparently) northwesterly oriented structural feature. This summer, Diamonds North drill-tested five magnetic features along the corridor. One hole hit six separate dyke-like intervals of kimberlite for a cumulative total of 15 metres. Another hole intersected three kimberlite intervals totalling 1.8 metres.
Diamonds North was unable to test a new kimberlite discovery it made at anomaly 5363. Thicker-than-usual overburden in the target area caused substantial drilling problems. One hole was lost in overburden, while two others ended prematurely in kimberlite after the drill rods twisted off. The company, however, managed to recover a “sufficient” sample for microdiamond analysis. The magnetic signature of the 5363 anomaly is 350 metres long and 100-150 metres wide.
Diamonds North also re-tested the Snow Bunting kimberlite, which was discovered by De Beers in 1997. De Beers recovered 23 micros from a 137-kg sample, based on a 0.5-mm2 mesh screen classification. Diamonds North pulled a 20-metre-long intercept of kimberlite from the Snow Bunting body, which it estimates to be 250 metres long and 10 metres wide.
Prospecting along the Galaxy corridor has uncovered outcropping kimberlite. Field crews recovered about 700 kg of kimberlite samples from surface exposures in three different areas. One of the sample sites is 300 metres from the Sand Piper body, whereas another is roughly 6 km to the northwest. Surface samples have been shipped to Lakefield Research for microdiamond analysis.
Diamonds North holds more than 5,620 sq. km on Victoria Island in the Arctic region of Nunavut and the Northwest Territories. The wholly owned Blue Ice property covers 809 sq. km.
Earlier this year, the diamond assets of
Early player
Major General was an early player on Victoria Island. Recognizing the possibility that the eastern half of Victoria Island was underlain by the northern extension of the Slave Craton, the company first acquired ground in 1994.
Monopros, the Canadian exploration arm of De Beers, began exploring Victoria Island in 1994, entering into a reciprocal access and earn-in agreement with Australia’s WMC on several permits. WMC was interested only in base and precious metals. Regional sediment sampling and mapping were carried out in 1994 and 1995, followed by a fixed-wing airborne geophysical survey in 1995. From 1996 to 1997, Monopros collected 833 heavy mineral samples consisting mostly of tills. Following further airborne work, a helicopter-borne magnetic survey was flown over anomalies of high interest. In 1997, Monopros tested 17 targets with 26 reverse-circulation holes totalling 1,128 metres and, in the process, discovered six kimberlite bodies, namely Jaeger, Turnstone, King Elder, Snow Goose, Sand Piper and Snow Bunting. Many of the details of these discoveries are only now being made public.
A review of De Beers’ drilling and geophysical data for the Snow Goose pipe leads Diamonds North to conclude that Snow Goose consists of two separate kimberlite bodies. Two of the original holes drilled at Snow Goose tested a discrete geophysical anomaly, whereas a third hole, drilled between the other two, encountered no kimberlite.
Gosling
Diamonds North has renamed the second discrete anomaly the “Gosling” kimberlite. A previously drilled vertical hole into Gosling intersected kimberlite from 16 to 110 metres of depth. From 151 kg of processed kimberlite, De Beers recovered 52 micros and three macros weighing an impressive 0.262 carat. Much of the recovered parcel weight is attributed to one diamond, which, along with eight other micros, weighs 0.23 carat.
Monopros discovered two more kimberlite pipes — Pintail and Sanderling — in 1998, north of the Major General and Ascot joint venture.
In March 1998, De Beers struck a deal with Major General and Ascot, and acquired the right to earn a 51% interest in the Victoria Island Washburn project by spending $2 million on exploration and paying $200,000 over three years. That summer, Monopros tested eight geophysical targets and discovered five new kimberlite bodies, all within 10 km of each other. These kimberlites, known as Phalarope, Golden Plover, Longspur, Snowy Owl and Whimbrel, were initially tested with short percussion holes, which penetrated only 5-11 metres into each pipe. Snowy Owl has since been tested to a depth of 130 metres.
Microdiamond results from the discovery holes were as follows:
q The Snowy Owl kimberlite returned a total of 85 micros and five macros from an 88-kg sample.
q A 200-kg sample from Golden Plover yielded 41 micros and six macros, including three stones greater than 0.5 mm in two directions. The largest diamond was a fragment measuring 1.51 by 1.05 by 0.63 mm.
q Longspur returned 61 micros and five macros, including four diamonds greater than 0.5 mm in two dimensions, from 100 kg of sample. The largest stone is an octahedron measuring 1.14 by 0.71 by 0.54 mm.
q Phalarope returned six micros from 180 kg of material.
q Whimbrel gave up just a single micro from 180 kg of tested kimberlite.
Data awaited
Lakefield Research described the larger microdiamonds recovered from Golden Plover and Longspur as clear, white, high-quality diamonds with little “resorbtion.” Diamonds North is awaiting the release of further data and the return of recovered diamonds from several kimberlites, including the Snowy Owl kimberlite pipe, from De Beers.
In early 1999, Monopros discovered two more kimberlites on the Washburn joint-venture property: the barren Arctic Tern kimberlite dyke and the diamond-bearing Horned Lark kimberlite body. After spending $1.3 million on exploration, De Beers walked away from the joint venture in February 2000 in the final year of its option. Major General later acquired De Beers’ winterized camp on Victoria Island and 29 mineral claims after the major pulled out of the region entirely. De Beers retains a 1.5% gross overriding royalty and the diamond marketing rights to any commercial operation producing 1 million carats per year from the claims.
Kolebaba believes there is still a lot of exploration potential on Victoria Island.
Underexplored
“It’s a big field and it’s very underexplored. Only 16 kimberlites had been tested when we got involved, and if you look at places like Ekati, where there are 140 odd kimberlites, only seven of them make the mine plan. The kimberlite indicator mineral chemistry in the region is very promising. The eclogitic garnets coming out of Victoria Island are as good as what you see over some of the best places in the Slave.”
During the summer 2000 field season at Washburn, Major General and Ascot uncovered a new narrow kimberlite dyke, dubbed Ptarmigan, while hand trenching. The 20-cm-wide dyke yielded 40 micros and five macros from 77 kg of surface sample.
The 245-sq.-km Washburn project is held 52% by Diamonds North and 48% by Ascot. A preliminary option agreement with
Instead,
Majescor can earn a half-interest by spending $2.2 million on exploration over three years. Diamonds North remains the operator.
A helicopter-borne magnetic survey is targeting, for follow-up, more than 15 geophysical anomalies selected from a previous high-resolution fixed-wing survey. Kimberlites at Victoria Island occur as distinct geophysical anomalies in the carbonate country rocks.
Foothold
“We believe that the partnership with Diamonds North on this exciting diamond play is very significant for our company as it gives Majescor a foothold in an underexplored region of the Archean Craton,” states Majescor President Jacques Letendre.
In the meantime,
In addition, a new, 1-metre-wide kimberlite dyke was intersected by two shallow holes on the Juno anomaly, representing a northwesterly trending linear feature. The joint venture also retested the King Eider pipe with two holes after ground magnetic surveying indicated it was significantly larger than estimated.
Angled at minus 50 to the east, the first hole struck 108 metres of kimberlite between a depth of 6 and 126 metres down-hole, including two 6-metre-wide limestone bodies, which may be large xenoliths. The rig was swung in the opposite direction and a hole angled at minus 50 to the west intersected 19 metres of kimberlite. Both holes ended in limestone country rock.
Initial field descriptions described the kimberlite unit as coarsely crystalline, olivine and phlogopite-rich macrocrystic kimberlite, and likely of diatreme facies. Both purple and orange garnets up to 6 mm in size are present, and these become more abundant with depth. Microdiamond counts remain pending.
Canabrava can earn a half-stake in the Hadley Bay project by spending $5 million on exploration over four years and issuing 250,000 shares to Diamonds North. A helicopter-borne geophysical survey was flown over a 326-sq.-km high-priority portion of the project at the end of August. In addition, some 30 recently staked isolated anomalies were surveyed individually.
Canabrava has engaged Haywood Securities to help carry out a $2-million financing by way of a private placement consisting of either flow-through or non-flow-through units priced at 18 apiece.
Diamonds North has several other joint ventures on Victoria Island, including the Yankee project, with
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