Tres-Or Resources Ltd. (TSX-V: TRS) (OTC: TRSFF) is pleased to announce Type II microdiamonds lacking measurable nitrogen dominate at the Guigues Kimberlite pipe in southwestern Quebec. The nitrogen measurements were conducted by the Saskatchewan Research Council Geoanalytical Laboratories Diamond Services (SRC) on all Guigues +0.150 mm microdiamonds, using the industry-standard technique of micro-Fourier Transform Infrared Spectroscopy (FTIR).

In total, SRC reports 14 out of the 17 +0.150 mm microdiamonds lacked detectable nitrogen (zero parts per million – 0 ppm), and thus are the highly desirable Type II. Type II diamonds are rare (less than 2% of gems sold) but highly desirable because many of the largest, highest quality gem diamonds ever recovered lack nitrogen (refer to Tres-Or news release dated December 8, 2020).

“Tres-Or is excited to learn that Type II microdiamonds dominate our samples. This is another positive factor, along with the microdiamond counts themselves, strong diamond indicator mineral chemistry and the site’s excellent access and infrastructure that are moving our Guigues Diamond Project forward towards our first macro-diamond tests, which we hope to announce in the near future,” says Laura Lee Duffett CEO of Tres-Or Resources Ltd.

SRC reports that the other 3 microdiamonds +0.150 mm-contain between 365 and 949 ppm nitrogen apiece, and are dominated by the “A” nitrogen crystal lattice defect suggesting relatively shallow mantle residence depths (SRC estimates between 150 and 165 km, using a 40 mW/m² geotherm).

Table 1: Nitrogen-free Type II diamonds out of total microdiamonds +0.150 mm square mesh screen.

As noted in Tres-Or’s news release of January 5, 2021, a total of 48 microdiamonds were recovered by SRC from 305 kgs of previously unsampled intervals of Guigues kimberlite drill core, with the largest two microdiamonds remaining on a 0.425 mm square mesh screen. SRC describes all but 3 of the recovered Guigues Kimberlite microdiamonds as “White/Colourless, Transparent” with no or minor inclusions. Only one microdiamond is described as having “noticeable inclusions”. Complete descriptions for the 17 Guigues +0.150 mm microdiamonds tested are provided in Table 2.

These Type II results are from microdiamonds recovered from 305 kgs of material processed at SRC for microdiamonds comprised of 3 samples from half-split drill core (HQ size) testing different parts of the pipe. The recovered microdiamonds are well distributed throughout the pipe. Out of 65 sample bags processed, 30 returned at least one microdiamond. The maximum number returned per batch was 9 and the second most prolific batch returned 5. The 13 bags comprising sample 047531 returned the most total microdiamonds at 22, suggesting the possibility of a higher grade phase in the southern part of the pipe, but more data is required to gain confidence in this possibility. Tres-Or will be looking to identify potentially higher grade kimberlite phases as additional sample data becomes available.

Table 2: Complete descriptions of nitrogen content and %A defect and Type II designation as determined by SRC’s proprietary FTIR data deconvolution methods. ppm = parts per million; wM/m² = milliwatts per square meter.

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.

Sampling Protocols:

Each sample was bagged successively by Tres-Or personnel, in approximately 8 kg sub-samples. The total sample interval extends approximately 26 m in length. After bagging and labelling, the samples were delivered to SRC in Saskatoon, Saskatchewan. The unsampled half split of core is stored securely for future reference. The ~8 kg bags were processed by SRC as separate batches and microdiamond recoveries were reported for each of the 8 kg bags. SRC reports microdiamond counts by square mesh screen sizes, increasing in succession from the smallest size (in this case 0.075 mm) upwards by a factor of the square root of 2, as specified in CIM reporting standards required under Canadian National Instrument 43-101 reporting standards. SRC also describes and reports dimensions as well as weights for each individual microdiamond.

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. Additional information related to the Company is available on SEDAR and on the Company’s website.