What’s CBE Worth, page-911

Also a few excerpts from below linked article (Analyst's Notes on Crux Investor website) regarding the XRF part:
https://www.cruxinvestor.com/articles/analysts-notes-week-15

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Although no laboratory assays are yet available, hand-held X-ray Fluorescence (“XRF”) measurements taken at regular 25 cm intervals (therefore non-selective) have given attractive results between 0.1 % Cu and 5% Cu over downhole sections of 59 m in NCP07, 25 m in hole NCP08, 15 m in NCP09 and 13 m in hole NCP10.
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Crux Investor cautions that the readings with a handheld XRF cannot be given the weighting of laboratory assays, but the fact that numerous readings were made at regular intervals (= unbiased), gives comfort.
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