Shear Diamonds Ltd.
TSX VENTURE : SRM

February 08, 2011 10:19 ET

Shear Reports Diamond Content Range Up To 11.3 cpt From Recovery Reject Tailings Audit at Jericho

EDMONTON, ALBERTA--(Marketwire - Feb. 8, 2011) - Shear Diamonds Ltd. (TSX VENTURE:SRM) today announced the confirmation of a sample grade of 11.3 carats per tonne ("cpt") from an internal audit of 308.8 kg of kimberlite concentrate from the recovery reject tailings at the Jericho Diamond Mine. A total of 52 macro diamonds representing 3.5 carats were recovered from a small sample collected across surface of the recovery rejects stockpile at the mine site, resulting in the sample grade of 11.3 cpt with the largest stone being a 0.54 carat diamond. during operations.

"These audit results allow us to begin to determine a better methodology for future processing of Jericho's kimberlite in order to achieve optimum diamond liberation and recovery," says Shear President Pamela Strand. "Also, we believe that based on these high diamond contents, that Jericho's recoverable diamond grade has the potential to increase substantially."

The results of the Shear audit is summarized in the following table.

Shear Recovery Rejects Audit:

Jericho Kimberlite Complex Weight of Tails Audited (kg) Weight of Diamonds Recovered (carats)
(+0.85mm)
Number of total stones +0.85
mm
0.85
mm Sieve
1.18
mm Sieve
1.70
 mm Sieve
2.36
mm Sieve
3.35 mm Sieve 4.75 mm Sieve Sample Grade cpt
Recovery Rejects – SRC 308.8 3.50 52 5 24 21 1 1 0 11.3

For the purposes of the 2010-2011 audit, the sample, processed at the Saskatchewan Research Council's Geoanalytical Laboratories Diamond Services ("SRC"), was fed into an High Pressure Grinding Roll ("HPGR") and crushed with a 4mm gap setting. The crushed concentrate was then run through a diamond recovery circuit consisting of an X-Ray Flowsort and Grease Table audit using a bottom cutoff size of 0.85mm. By reprocessing a small sample of recovery reject tailings through an HPGR crush and recovery circuit, Shear was aiming to establish the presence of possible locked diamonds (those that were not liberated by the original crushing circuit and remain trapped in kimberlite).

The purpose of Shear's mini-audit was to confirm the results of a 4,048.5 kg sample from the recovery reject stockpile collected by Tahera Diamond Corporation ("TDC") in late 2007, which yielded 1,345 stones weighing 58.8 carats for a sample grade of 14.5 cpt. The largest recovered stone weighed 0.94 carats. This sample was treated at SGS Lakefield Research Limited ("SGS") using a similar recovery circuit with a re-crush down to 4mm, and a 2-pass X-Ray Sortex and 2-pass grease table audit. Screened material +1mm to -4mm was run through a magnetic separator and diamonds from the non-magnetic material were recovered by caustic fusion due to the large volumes of concentrates.

TDC had also submitted a 1,345 kg sample of coarse processed kimberlite ("CPK") tails to SGS for audit purposes in 2007. The sample was run through a Dense Media Separation ("DMS") circuit with an HPGR re-crush at a 4mm gap setting, and a bottom screen size of 0.85mm. The sized concentrate underwent HIMS (magnetic separation) processing and the non-magnetic fractions were then hand sorted for diamonds. A total of 45 stones weighing 1.14 carats were recovered for a sample grade of 0.84 cpt. The largest recovered stone weighed 0.22 carats.

TDC conducted a much larger on-site audit of the CPK (approximately 11,000 tonnes) which was suggestive of similar results as outlined below. Estimates from the historic mine records of process plant by-products for the recovery rejects and CPK are 25,000 tonnes and 900,000 tonnes respectively. A portion of the CPK was used for construction purposes and is no longer accessible for re-processing and recovery of diamonds.

The results of the past audits are summarized in the following table.

Results of Past Recovery Reject and CPK Tailings Audits:

Jericho Kimberlite Complex Weight of Tails Audited (kg) Weight of Diamonds Recovered (carats)
(+0.85mm)
Number of total stones +0.85
mm
0.85
mm Sieve
1.18
mm Sieve
1.70
 mm Sieve
2.36
mm Sieve
3.35 mm Sieve 4.75 mm Sieve Sample Grade cpt
Recovery Rejects – SGS (2007) 4,048.5 58.77 1,345 271 861 182 25 6 0 14.5
CPK Tails – SGS (2007) 1,345.5 1.14 45 30 12 3 0 0 0 0.8

About Shear Diamonds Ltd.

Shear is a Canadian-based company focused on diamond exploration and development in Canada's North, where it explores established diamond districts and has discovered new ones. Shear currently has a portfolio of eight diamond projects, including three advanced projects with development potential. Shear holds a 100% interest in its recently acquired Jericho Diamond Mine and surrounding exploration assets, located in the Kitikmeot region of Nunavut. Jericho is Nunavut's first and only diamond mine.

Pamela Strand, P. Geol., Shear's President and Chief Executive Officer, and Jennifer Burgess, P. Geo. Shear's VP Exploration, are qualified persons for purposes of National Instrument 43-101 who supervised the preparation of the information forming the basis for this press release.

On behalf of the Board of SHEAR DIAMONDS LTD.

Pamela Strand, P. Geol., President & CEO

Julie Lassonde, Executive Chairman 

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 Shear's expectations are in its documents filed from time to time with the TSX or the TSX Venture Exchange and provincial securities regulators, most of which are available at www.sedar.com. Shear disclaims any intention or obligation to revise or update such statements.

The TSX Venture Exchange has not reviewed and does not accept responsibility for the adequacy or accuracy of this release.

Contact Information

  • Shear Minerals Ltd.
    Pamela Strand, P. Geol.
    President and CEO
    (780) 435-0045 or 1-866-298-9695
    www.shearminerals.com