Stornoway Diamond Corporation (TSX-SWY) is pleased to provide complete diamond recovery results from the Renard 4 kimberlite, the third individual kimberlite bulk sample to be completed as part of the Renard bulk sample program in north-central Québec. Stornoway, and 50:50 joint venture partner SOQUEM INC. ("SOQUEM"), have successfully completed a program of sampling at Renard designed to recover a minimum 6,000 carats of diamonds from three separate kimberlite pipes. Renard 4 has now returned a total of 2,213 carats of diamonds from five separate sub-samples with a combined dry sample weight of 1,659 tonnes, representing an overall diamond recovery of 133 carats per hundred tonnes (cpht) for stones retained on a +1 DTC screen. Diamond recovery from individual sub-samples varied between 80 cpht and 184 cpht, with the largest diamond weighing 5.92 carats. Complete Renard 4 diamond data, after utilizing both x-ray sorter and grease table recovery circuits, are as follows:
Sub-Sample |
Dry
Weight
(tonnes)
|
Stones
(retained on +1
DTC screen)
|
Carats
(retained on +1
DTC screen)
|
Diamond
Content1
(cpht)2
|
Largest
Diamond
(carats)
|
R4-4001 |
366.0
|
3,674
|
368.41
|
101
|
3.71 |
R4-4002 |
459.4
|
6,179
|
607.98
|
132
|
5.92 |
R4-4004 |
233.4
|
1,901
|
187.09
|
80
|
2.56 |
R4-4005 |
509.6
|
9,708
|
938.20
|
184
|
3.70 |
R4-4006 |
90.6
|
989
|
111.57
|
123
|
2.18
|
Total |
1,659.0
|
22,451
|
2,213.25
|
133
|
|
1The estimated diamond content, expressed as carats per hundred tonnes, may not be representative of the overall diamond content of the body due to a number of factors, including location/size of the samples and processing parameters
Diamond recovery from the Renard 2, 3 and 4 bulk sample program is now complete. A total of 6,497 carats have been recovered from 6,036 dry tonnes of processed kimberlite. A sufficient parcel of diamonds has now been recovered from each of Renards 2, 3 and 4 to proceed to an independent, open market valuation exercise. It is anticipated that this will occur in September 2007, with results expected early in the fourth quarter. Complete diamond recovery results from the Renard bulk sample program are now as follows:
Kimberlite Pipe
|
Dry
Weight
(tonnes)
|
Stones
(retained on +1
DTC screen)
|
Carats
(retained on +1
DTC screen)
|
Diamond
Content1
(cpht)2
|
Largest
Diamonds
(carats)
|
Renard 2 - Kimb2a3 |
1,778.3
|
7,250
|
857.83
|
48
|
4.90, 4.47, 4.27 |
Renard 2 - Kimb2b3 |
670.5
|
6,534
|
744.15
|
111
|
15.46, 8.80, 8.42 |
Renard 34 |
1,928.6 |
25,682
|
2,681.40
|
139
|
10.15, 7.78, 6.36 |
Renard 4 |
1,658.9 |
22,451
|
2,213.29
|
133
|
5.92, 3.71, 3.70 |
Total |
6,036.4 |
61,917
|
6,496.66
|
108
|
|
1 The estimated diamond content, expressed as carats per hundred tonnes, may not be representative of the overall diamond content of the body due to a number of factors, including location/size of the samples and processing parameters
2 Carats per hundred tonnes
Eira Thomas stated, "The latest bulk sample results at Renard have confirmed a high grade zone at the northern end of Renard 4, with a diamond content 27% higher than previous, reported results in this area. Overall, diamond recovery from the Renard bulk sample program has exceeded our expectations. The successful completion of this phase of the program now allows us to proceed to a market valuation of the Renard diamonds ahead of a NI 43-101 compliant resource calculation to be undertaken later in the year. This will be the first formal resource statement at Renard, and an important milestone in the road towards Québec's first diamond mine."
The five largest diamonds recovered from Renard 4 are a 5.92 carat brown octahedron, a 3.71 carat light off-colour makeable, a 3.70 carat brown clivage, a 3.67 carat light off-colour gem octahedron, and a 3.38 carat colorless gem octahedron. Photographs of these diamonds can be found on the Stornoway website at http://www.stornowaydiamonds.com/news/2007/renard4/.
Renard 4 Geology
The five individual sub-samples from Renard 4 reported above were collected from a trench developed upon a northern, "complex" zone of the pipe, which is exposed close to the surface under a thin till cover. Previous sampling of this zone had indicated that it was comprised of higher grade material than the rest of Renard 4, and presented an opportunity to collect a sample of diamonds large enough for a statistically meaningful diamond valuation. Mapping within the trench has outlined several geological units within this zone, including a tuffisitic kimberlite breccia, hypabyssal kimberlite dykes, country rock breccias and granite. Only the tuffisitic kimberlite breccia and the hypabyssal kimberlite were sampled. Delineation drilling suggests the complex zone has a depth extent of at least 188 and has the potential to contribute a meaningful proportion of high grade kimberlitic material within a Renard 4 resource model.
Recovered diamond content from individual sub-samples, and the complete Renard 4 trench sample, does not conform to the definition of a "mineral resource" grade established by National Instrument ("NI") 43-101. Stornoway is in the process of establishing detailed geological models for each of the Renard kimberlites to be utilized in a subsequent NI 43-101 compliant resource calculation. As a component of this work, individual geologic units observable within the pipes will be reconciled with diamond recovery information.
Comparative Historical Data
Between 2004 and 2006, Stornoway's wholly owned subsidiary Ashton Mining of Canada Inc. ("Ashton") and its JV partner SOQUEM collected a series of samples from the northern complex zone of Renard 4 by core drilling, reverse circulation drilling and surface sampling that returned diamond contents of between 85 and 175 cpht, with a weighted average of 105 cpht. The largest diamond recovered during these programs was a 1.71 carat off-white octahedron.
Historical diamond recovery results now reported from the northern zone at Renard 4 are as follows:
Disclosure Date
|
Dry Weight
(tonnes)
|
Carats
|
Diamond
Content2
(cpht)3
|
Largest
Diamonds
(carats)
|
August 14, 20074 |
1,659.0
|
2,213.25
|
133 |
5.92, 3.71, 3.70 |
August 23, 20061 |
2.88 |
4.975
|
173 |
0.61 |
June 26, 20061 |
40.60 |
34.45
|
85 |
1.71 |
October 5, 20051 |
7.39 |
12.785
|
173 |
0.67 |
December 22, 20041 |
1.77 |
3.095
|
175 |
0.16 |
1 Reported by Ashton Mining of Canada Inc.
2 The estimated diamond content, expressed as carats per hundred tonnes, may not be representative of the overall diamond content of the body due to a number of factors, including location and size of the samples or drill holes
3 Carats per hundred tonnes
4 Represents only stones retained on a +1 or greater DTC screen, as discussed below
5 Represents only stones retained on a +1.18 mm square mesh screen
Scientific and Technical Data
Diamond results reported in this release are based on sample processing by a 10 tph DMS plant owned by Stornoway (through Ashton) and SOQUEM in joint venture, and operated by Stornoway, and on the recovery of diamonds from concentrate at Stornoway's wholly owned and operated mineralogical laboratory in North Vancouver, British Columbia. Quality assurance protocols and actual operating procedures for the processing, transport and recovery of diamonds under the Renard bulk sample program, including arms-length security provisions, conform to industry standard Chain of Custody provisions and are subject to the review of AMEC Americas Ltd. who have been contracted to provide third party accreditation for program data.
For the Renard bulk sample program, individual kimberlite samples are prepared through a primary jaw crusher prior to introduction to the 10 tph DMS. To facilitate production of a heavy mineral concentrate, -20mm material is fed directly into the DMS and +20mm material is reduced through a secondary cone crusher set at 10mm. DMS coarse reject "floats" are re-crushed to -6mm and re-circulated through the DMS. During the processing of the initial portion of Renard 4 sub-sample R4-4001 a 1.2mm by 13.0mm slotted screen was employed. The subsequent four Renard 4 samples and the remaining portion of R4-4001 were processed utilizing a 1.0mm by 12.0mm slotted screen. Use of the 1.0mm by 12.0mm slotted screen would slightly increase recovery of smaller diamonds, but the minimum stone size would still be greater than that retained on a +1 DTC screen. Following delivery to North Vancouver, the resultant DMS concentrate was then processed twice through x-ray sorter equipment to generate a final concentrate which was hand sorted to extract diamonds. A grease table finish was used to recover diamonds from all x-ray sorter rejects. Diamonds were recovered from (a) two x-ray sorter passes and (b) the grease table recovery circuit. Diamond recovery reported above pertains only to stones retained on a +1 DTC screen, approximately equivalent to a 0.85mm square mesh screen. However, the bottom cut-off screen sizes used on the DMS will result in under-recovery of smaller diamonds and will not allow a direct comparison with previously reported diamond contents. As part of Stornoway's ongoing QA/QC program, DMS tails, concentrate residues and other materials are also subject to audit. Any significant changes to the recovered diamond grades provided above will be reported when available. The Renard bulk sample program is managed by Dave Skelton, P.Geol., Senior Project Manager. Stornoway's diamond exploration programs are conducted under the direction of Robin Hopkins P.Geol, Vice President, Exploration, a Qualified Person under NI 43-101.
Stornoway Diamond Corporation
Stornoway Diamond Corporation is one of Canada's leading diamond exploration and development companies, involved in the discovery of over 150 kimberlites in six Canadian diamond districts. The Company benefits from a diversified diamond property portfolio, a strong financial platform and management and technical teams with experience in each segment of the diamond "pipeline" from exploration to marketing.
SOQUEM INC.
SOQUEM is a wholly-owned subsidiary of Société générale de financement du Québec ("SGF"). The SGF, the Quebec industrial and financial holding company, has as its mission to undertake economic development projects in the industrial sector in cooperation with partners and in compliance with the economic development policies of the Government of Quebec.
On behalf of the Board
STORNOWAY DIAMOND CORPORATION
/s/ "Eira Thomas"
Eira Thomas
Chief Executive Officer
This news release may contain forward looking statements, being statements which are not historical facts, including, without limitation, statements regarding potential mineralization, exploration results, resource or reserve estimates, anticipated production or results, sales, revenues, costs, "best-efforts" financings or discussions of future plans and objectives. There can be no assurance that such statements will prove accurate. Such statements are necessarily based upon a number of estimates and assumptions that are subject to numerous risks and uncertainties that could cause actual results and future events to differ materially from those anticipated or projected. Important factors that could cause actual results to differ materially from the Company's expectations are in Company documents filed from time to time with the Toronto Stock Exchange and provincial securities regulators, most of which are available at www.sedar.com. The Company disclaims any intention or obligation to revise or update such statements.