Twin Mining shareholder gushes over Jackson Inlet diamonds

Antwerp-based Diamond Trading N.V. has provided Twin Mining (TWG-T) with a glowing assessment of 86 diamonds found in a 18.41-tonne sample collected from the Freightrain kimberlite at the Jackson Inlet property on Baffin Island in Nunavut, even suggesting they are of better quality than diamonds being produced at Canadian and South African mines. The Belgian firm is a minority shareholder of Twin Mining, having taken down an equity position of more than 1 million shares late last year.

Unlike kimberlites being mined in the Northwest Territories and elsewhere in the world, the Jackson Inlet sample is reported to contain no boart (industrial diamonds) or other types of low-grade and low-yield diamonds. Typically, primary kimberlite deposits contain far more industrial and poor-quality stones than gems and near-gems, and far more small stones than large ones. The exception is alluvial deposits, which are noted for their high concentrations of gem-quality stones.

Art Ettlinger, mining analyst for Yorkton Securities, cautions that the findings are not an independent appraisal. “Second, this is the first time, that we are aware of, that qualitative diamond valuations by diamantaires are being placed in the public domain. Given these two considerations, we are not sure what to make of the descriptions of the Jackson Inlet stones.”

Hermann Derbuch, president, says the diamonds were extracted from trenching and sampling of the Freightrain pipe on Brodeur Peninsula and that all 892 diamonds recovered to date feature the same characteristics as noted by Diamond Trading.

The Belgian firm says Freightrain diamonds are similar in quality to high-quality South African diamonds, “but without having their characteristic yellow colouring.” It went on to state that, in comparison to Slave Craton diamonds (from the Ekati and Diavik projects), “which are generally octahedrons with higher occurrence of black piques (impurities) and maccles (intergrown diamond crystals),” the Jackson Inlet sample “differs in the total absence of boart, rejections, coated and cubes, which are low-grade and low-yield diamonds.” The firm also saw no evidence of small feathers (crystal flaws) that appear across the range of Slave Craton diamonds.

Diamond Trading went on to suggest that the absence of feathers, impurities and colouring in the better half of the Freightrain sample, “combined with their rounded shape, will produce high yielding polished diamonds of good lustre, high purity and colour grading . . . [and] at a much higher proportion of the sample than is current in South African and Canadian kimberlite mine production.”

Derbuch says the Freightrain kimberlite also has an exceptional number of large diamonds — compared with other producers in the world, almost double the percentage of stones over 1 mm in size. “It’s still a small sample, and by no means representative, but it shows a pattern.”

While Twin Mining has not yet drilled the Freightrain kimberlite or any other targets at Jackson Inlet, the diamonds recovered to date are unlike anything previously found in Canada’s High Arctic. In the 1970s, a unit of De Beers Consolidated Mines found several weakly diamondiferous pipes there, and bulk-sampled several on Somerset Island before abandoning the project.

In the early 1990s, Charles Fipke’s Lac de Gras discoveries triggered renewed interest in Baffin Island and nearby Somerset Island. Twin Mining’s land package on Brodeur Peninsula was previously explored, first by Cominco, and later by Lumina Resources. No major discoveries were reported.

In early 1993, Citadel Gold Mines acquired ground elsewhere on Brodeur Peninsula and focused its efforts on a raised beach, where it hoped to recover diamonds eroded from nearby kimberlites. No preferential concentration of alluvial diamonds was found. About the same time, several of Murray Pezim’s juniors explored a previously known kimberlite on Brodeur Peninsula, again with little success. A few years later, Mountain Province Mining (mpv-t) and Opus Minerals found a kimberlite cluster on the northern end of Baffin Island, though subsequent sampling pointed to low grades.

Baffin Island popped back on the radar screen in the summer of 1998, when prospector Fred Tatarnic found a 0.768-carat diamond in weathered kimberlite. A subsequent 26.45-kg sample yielded 13 microdiamonds and two macrodiamonds. Twin Mining signed an agreement last April to acquire the ground for cash and shares from Helix Resources, a private company associated with Tatarnic (T.N.M., July 30-Aug. 5/01).

Senior Manager Dallas Davis visited the property in the following month and collected a 94.5-kg sample of weathered surface material from a 10-by-10-metre patch of bare ground. It yielded 36 micros and three macros. Trenching and sampling followed, with more than 800 diamonds recovered to date. The company recently began its first drilling program to test the kimberlite at depth.

Derbuch says the Jackson Inlet diamonds are not comparable to stones found in previously discovered pipes on Baffin Island and Somerset Island, with respect to either quality or size distribution, and are more similar to West African production. Recent sampling at Jackson Inlet has produced several commercial-sized stones, including one weighing one carat, from surface material.

Earlier this year, under the supervision of Davis, Twin Mining excavated a 16.5-tonne sample from the Freightrain kimberlite. It returned 74 stones in excess of 1 mm weighing 3.084 carats. A 1.9-tonne sample extracted from a site 100 metres distant yielded 12 diamonds weighing 0.56 carat. Sampling guidelines were established by MPH Consulting, and processing procedures were monitored by MRDI Canada.

Twin Mining has yet to explore other kimberlites at Jackson Inlet, including 12 potential targets identified by prospecting and traversing with a Beep Mat.