Whole sampling more representative

This letter is in response to your misleading and erroneous portrayal of “whole sampling” core as questionable sampling, with implications of “salting” and fraud in articles and cartoons (May 15 to July 10) regarding the Bonanza Ledge discovery made by International Wayside Gold Mines.

The purpose of every sampling program is to obtain an accurate measure of contained elements. I will not delve into the historical debates relating to sampling gold deposits and drilling methods, nor the obvious reasons why larger-volume samples are more representative. Similarly, I will not go into the details of the subsequent checks by geologists from several major companies, governments and Panterra Resources, all of whom verified the Bonanza Ledge results. I will also not debate the common practice of geologists to split or saw core, the purpose of which is to preserve and exhibit the geologic record for other geologists and assorted looky-lous to examine.

I do purport that it is virtually impossible to obtain a representative sample from broken fissile or schistose core by conventional manual core splitting or sawing — hence “whole sampling,” when the entire core obtained within a selected sample interval is taken, bagged and sent to the lab.

Five feet of BQ [36.5-mm diameter] core weighs approximately 5 kg, or 5,000 grams — 30 grams of which disappear in analysis, leaving 4,970 grams (99.4%) of the sample available in the form of reject and pulp. A sampling protocol including crushing, riffle splitting, and storing reject crushed rock and pulp is used by virtually all assay labs on all rock samples, whether core, percussion chips, grab samples or what-have-you.

The integrity of the “reject” is exponentially greater than that of split or sawn core, returned to a box to be picked over, misplaced, pocketed or otherwise lost in the shuffle of handling by numerous looky-lou tours. The reject can be used for check assaying, metallurgical tests, and acid-base accounting studies. The chips can be mounted and made into polished sections for mineralogical determinations. The chips are roughly the same size as those from percussion drilling, which are routinely logged using binocular microscopes or hand lenses. So much for the fallacy you perpetuate: that with no core in the box, there is no way of checking and no physical record of the sample.

Returning to “questionable methodology,” I submit that with whole sampling:

– the sample is more representative, owing to the volume (all instead of half);

– the human quandary of which portion to bag is eliminated;

– the sampler has a far superior method of obtaining a representative sample when dealing with broken or friable core, and hence produces a more reliable assay; and

– when the material is crushed and then split using a riffle splitter, there is a more representative, reliable result than that obtained from splitting or sawing even competent core.

When the entire sampling procedure is handled by a reputable lab, any question of salting should be eliminated. At Wayside, as an additional check and indicator, sludge samples (drill cuttings) were routinely collected at 10-ft. intervals and assays reported along with core assay numbers. Although sludge values are not touted as representative, they are definite indicators of mineral content in the zone and are independent samples.

The main detriment of “whole sampling” is that there is no geologic section preserved in core, nothing for the looky-lous to see nor for the geologist to re-examine after assay results are received.

With respect to Bonanza Ledge, it was obvious from the onset that this would become a multiple-drill-hole project with an abundance of similar core to follow. Although a conscientious effort was made to preserve a geologic section from the discovery holes, this was of secondary importance to obtaining representative samples and reliable results.

As to any comparison with the Indonesian fraud, I must give the analyst some credit for recalling it had something to do with sampling and security. The company in question apparently conducted all its own sample preparation in a highly secure compound and sent only the rumoured salted [gold-added] pulp portion to the lab for analysis. However, any similarity to Wayside, which left sample preparation entirely to the lab, eludes me.

I hope this enlightens you and ends your persistent attack on my professional credibility and personal integrity, as I was the “qualified person” in charge of the discovery at the time of the offences you allege. (I have 30 years of experience as a geologist, of which 15 were spent in development and production at gold mines. In addition, I exercised options and sold all my stock a month prior to the discovery hole.)

If not, please step from behind the cover of the libel law protecting newspapers and get personal.

Your unfounded “scam” attacks have not only had an extremely detrimental effect on my sense of humour but also on the efforts of every gold exploration company that depends on investor confidence.

Robert Reid

Wells, B.C.

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