Vancouver, B.C. – December 8, 2020 - Tres-Or Resources Ltd. (“Tres-Or” or the “Company”) (TSXV: TRS, OTCPK: TRSFF) is pleased to announce that the two largest of the Company’s recently reported microdiamonds recovered from the Guigues Kimberlite in southwestern Quebec are very low nitrogen (Type II) diamonds, as revealed by micro-fourier transform infrared (MFTIR) spectroscopy analysis at the Saskatchewan Research Council’s (SRC) Diamond Laboratory.

Type II diamonds lack nitrogen and famously include some of the largest, highest quality diamonds recovered at mines around the world (e.g. including the historic 1,758 Sewelô, the 1,109 carat Lesedi La Rona and the 813 carat Constellation diamonds from the Karowe Mine in Botwsana, as well as the famous +3,000 carat Cullinan diamond from the Premier Mine in South Africa), although they are rare and only make up an estimated 1 to 2% of diamond production world-wide (Table 1).

Table 1: Famous Type II diamonds from mines around the world (see references at end).
Diamond Mine Locations Carats Famous for: (All US$) Notes
Cullinan diamond Premier Mine South Africa 3107 Largest gem diamond in history British Crown Jewels
Sewelô Karowe Mine Botswana 1758 2nd Largest gem diamond in history Discovered 2019
Lesedi La Rona Karowe Mine Botswana 1109 3rd largest gem diamond in history
(sold for $53 million)
Discovred 2015
Constellation Karowe Mine Botswana 813 sold for $63.1 million Discovred 2016
Sethunya Karowe Mine Botswana 549 "exceptionally pure high color" Discovered Feb 2020
Lesotho Legend Letseng Mine Lesotho 603 D flawless - rounded irregular shape Discovered 2006
Lesotho Legend Letseng Mine Lesotho 910 D flawless - 5th largest gem in history Discovered 2018
Flawless D color Victor Mine Ontario 271 2nd largest oval cut diamond 102 carats Discovered 2018

Note that although the recovery of Type II microdiamonds from the Guigues Kimberlite is suggestive of the occurrence of larger stones, this does not mean that the Guigues Kimberlite will necessarily host large Type II diamonds.

SRC’s analysis determined the two Type II stones from Guigues carry zero (0) ppm nitrogen. The stones were the largest of the microdiamonds recovered by SRC (as reported in Tres-Or’s news release dated November 9, 2020). The larger of the two Type II microdiamonds remained on the 0.300 mm square mesh screen, and the other remained on the 0.212 mm screen. Micro-FTIR spectra were recovered for the two microdiamonds that remained on the 0.150 mm screen as well. These two microdiamonds carried 660 and 595 ppm nitrogen respectively, and are interpreted to have experienced mantle temperatures and pressures consistent with the diamond stability window (see Table 2).

Table 2: MFITR data including estimated nitrogen (N) content, mantle temperatures (T), pressure (P) and depths (kms). Note: Lack of N in the Type II diamonds preclude calculations of P and T.
38 mW/m2 geotherm
IaA (%)
IaB (%)
N (ppm)
3 Ga
Pressure (GPa)
Depth (km)
530 150um
530 150um
532 212um
532 300um

The remaining 6 microdiamonds recovered by SRC from the first Guigues microdiamond tests remained on a 0.106 mm screen, and were too small to yield a reliable micro-FTIR spectra.

Additional new microdiamond samples from the Guigues Kimberlite are currently in process at SRC. Results, including counts and nitrogen contents, will be reported as soon as available.

See Tres-Or’s website ( for more details on the Guigues Kimberlite Pipe including indicator mineral chemistry plots, kimberlite descriptions and reference details.


Bowen, D.C., Ferraris, R.D., Palmer, C.E., and Ward, J.D. 2009. On the unusual characteristics of the diamonds from Letseng-la-Terae kimberlites, Lesotho. Lithos, v. 112s, pp. 77-4.

Karowe diamonds:

McCoy, K., 2018. That 910-carat diamond sells for cool $40 million.

About Tres-Or Resources Ltd.

Tres-Or Resources Ltd. is a Canadian resource company focused on exploring for diamonds and gold resources in the Témiscamingue and Abitibi regions of Québec and is listed on the TSX Venture Exchange under the trading symbol “TRS”. Additional information related to the Company is available on SEDAR and on the Company’s website (

On behalf of the Board of Directors

“Laura Lee Duffett”

Laura Lee Duffett, P.Geo.
President and CEO

For further information

Laura Lee Duffett, President & CEO: +1 (604) 541-8376 –
Dean Claridge, Business Development: +1 (604) 688-8700

Neither the TSX Venture Exchange nor its Regulation Service Provider (as the term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this news release.

Qualified Persons

Disclosure of a scientific or technical nature related to the Company’s projects and exploration activities in this news release was prepared under the supervision of Dr. Harrison O. Cookenboo, B.Sc., M.Sc., Ph.D., P.Geo., the Company’s independent Qualified Person (as such term is defined in National Instrument 43-101), and Ms. Laura Lee Duffett, P.Geo., the Company’s President and CEO, who is a non-independent Qualified Person, both of whom have reviewed and approved the technical and scientific portions of this presentation.

Forward-Looking Statements

This news release contains projections and forward-looking information that involve various risks and uncertainties, including, without limitation, statements regarding the potential extent of mineralization, resources, reserves, exploration results and plans and objectives of the Company. These risks and uncertainties include, but are not restricted to, the early stage development of the Company and its projects; general business, economic, competitive, political and social uncertainties; capital market conditions and market prices for securities, junior market securities and mining exploration company securities; commodity prices, the amount of geological data available, the uncertain reliability of drilling results and geophysical and geological data and the interpretation thereof and the need for adequate financing for future exploration and development efforts. There can be no assurance that such statements will prove to be accurate. Actual results and future events could differ materially from those anticipated in such statements. These and all subsequent written and oral forward-looking statements are based on the estimates and opinions of management on the dates they are made and are expressly qualified in their entirety by this notice. The Company assumes no obligation to update forward-looking statements should circumstances or management's estimates or opinions change.