Exploration Insights
by Brent Cookwww.explorationinsights.com
Issue No. 152
July 31, 2011
Normally Exploration Insights is exclusive to subscribers and we appreciate that you don’t cut and paste or forward the timely information herein. However, as soon will become clear, the Rant in today’s letter is for general distribution and you are welcome to send it along to anyone you think may be interested its subject (if you would prefer a .pdf send us an email).
The Rant
US Based Newsletter Writer Clarifies Bayfield Ventures’ Clarification of Misinformation Regarding Potentially Confusing Drill Information that Bayfield Clarified in a Previous Confusing Release as Mandated by BCSC
On Tuesday, July 26 a US based newsletter writer was asked during this BNN interview (Tuesday, 11:50 EST) to comment on Bayfield Ventures’ (BYV.TSX-V) potentially confusing drill results. Subsequent to his comments, Bayfield distributed this news release in which they stated that factual errors were made by said newsletter writer in the discussion.
Let’s get factual
In their June 30 news release, Bayfield Ventures reported that the British Columbia Securities Commission (BCSC) required BYV to “clarify” certain details of its technical disclosure of previously released drill results. The “potentially confusing” information in question relates to BYV’s reporting of long intervals of mineralized drilling results that were created by diluting a few, sporadic high grade intercepts with lengthy intervals of lower grade (and even some barren) intercepts. This equates to a mathematical smearing of the isolated high grade intervals throughout a larger volume of low and possibly sub-economic material. By smearing gold grades, the character of the geologic occurrence is misrepresented and can be confusing and/or misleading to the general public who, on the whole, don’t have the tools or experience to recognize this mathematical misrepresentation. (We have examined this issue many times here at Exploration Insights using the free drill interval calculator.)
That was the gist of the BNN conversation. BYV was not represented as the “poster child” of smearing; rather, their recent press releases and the restatement required by the BCSC merely made them a timely example for a respected daily business show.
With respect to the BCSC mandated clarification-- this addresses five drill holes from four separate news releases dated September 8, 2010 to June 27, 2011. Specifically*:
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Sept 8, 2010 RR10-18: BYV reported 81 meters grading 5.08 g/t Au, between 488 to 569 meters drill depth; this was restated to 13 meters of high-grade contained in three separate intervals (see table below). 
- Dec. 14, 2010 RR10-52: (My personal favorite, with erratum to the BNN discussion where I misstated 80 meters, rather than 58) BYV reported 58 meters grading 1.84 g/t Au between 394 to 452 meters drill depth; this was restated as 1.1 meter grading 89.96 g/t Au, at 402.4 meters depth.
- Feb. 16, 2011 RR11-1: BYV reported 116.6 meters grading 1.05 g/t Au between 509 meters to 626 meters drill depth; this was restated as 20.8 meters containing three, isolated, high-grade intercepts.
- June 27, 2011 RR11-70: BYV reported 43.8 meters grading 1.02 g/t Au between 41.00 to 84.80 meters depth; this was restated as two separate higher grade intervals totaling 10.4 meters.
- June 27, 2011 RR11-71: BYV reported 79.5 meters grading 8.66 g/t Au between 15.50 meters to 95 meters depth; this was restated as 25.5 meters grading 26.7 g/t. Both drill holes 70 and 71 are good drill intercepts, the significance of which is dependent upon pending results from nearby holes.
- Yet to be restated: RR11-14: 56.9 meters grading 0.62 g/t between 275 to 328.3; should be two separate intervals of about 3 meters each grading 6.75 and 2.14 g/t.
*Note that we are only considering gold assays, as some of the earlier releases did not include silver assays.
(Fig. 1- One-year BYV chart showing news release dates for drill results that were subsequently “clarified”, and the apparent market reaction to original news releases)
Summarizing:
1. 81 meters becomes 13 meters beginning at 488 meters drill depth;
2. 58 meters becomes 1.1 meter beginning at a drill depth of 402 meters;
3. 116 meters becomes 20.8 meters beginning at a drill depth of 509 meters;
4. 79.5 meters becomes 26.5 meters beginning at a drill depth of 38 meters;
5. 43.8 meters becomes 10.4 meters beginning at a drill depth of 41 meters.
On July 19, some of these restated results from the June 30th clarification news release were posted to BYV’s website in a cross-section, as represented below (Fig. 2). The section actually appears to run slightly east of north, so the section may not be truly perpendicular to the strike of the feature; the true width may be somewhat less than drill width. I have edited the cross-section by including the approximate location of the long “mineralized” intervals as originally reported by Bayfield on the drill trace against the restated intervals where possible. This graphic visualization helps put some context to the restated mineralized intervals.
(Fig. 2- Burns Block Cross Section showing drill hole trace and mineralized intervals. The red bars represent the actual location of the mineralized intervals as restated in the June 30 news release. The length of the red bar is proportional to the grade. I added the green on the drill trace to represent the approximate drill interval the mineralization in red was smeared across in previous news releases. Note 50-meter scale on drill trace. So, does the green convey a different impression of the mineralization than the red?)
A key takeaway from the cross section is that, with the exception of mineralization intersected in RR-70 and 71, these high grade intersections are deep and, based upon the presently available information, would not be exploited via open pit mining. It is also very obvious that some of the “clarified” results are very narrow, high grade hits that were mathematically smeared over greater drill length —specifically RR-52—just as the BCSC noted.
The other topic discussed in the BNN segment relates to continuity of grade. In the cross section above, and in previous releases, BYV suggests that their drilling has identified a high grade gold shoot with a down plunge length of about 600 meters. Basically, BYV has connected the red bars on the drill holes above and are interpreting that these form a continuous mineralized body. The distance extrapolated between drill holes is up to about 100 meters – this is a big distance to extrapolate in deposits of this type. It will take considerably more infill drilling to prove continuity.
Bayfields’ location map suggests to me that there may be other drill holes that cross their section of choice, but that are not included; however, there is insufficient information to be certain, or to know why BYV selected the holes they used (the drill map is here for anyone interested). If drill hole data relevant to interpreting continuity are missing, one needs to ask why potentially useful data are omitted. Regardless, at this stage I am dubious about grade continuity of this projected shoot-- only time will tell.
There does, however, appear to be sufficient drilling immediately east and west of Bayfields’ section to establish or negate continuity along strike (Fig. 3). In some instances, gold ore bodies have continuity down plunge or dip which can be matched along strike. Basically, if an ore body is extensive or continuous in one direction it can be in the other as well; therefore, it is possible that we can use that on-strike data to guess at the down plunge continuity.
(Fig. 3- North Drill Fence map extracted from complete map, showing drill hole locations. Note the number of holes per location. Red are “high grade” holes, orange are drilled with assays complete, and yellow with assays pending. What is in the holes immediately adjacent to those selected for BYV’s cross section?)
The cross section in Figure 2 above is only a paper-thin two dimensional slice through the earth lined up along the holes BYV selected. Bayfield has drilled many dozens of holes along east west lines, usually with several holes from the same location. In order to evaluate the 600-meter long ore shoot BYV is postulating, we need to establish the east-west strike length of this zone. Although difficult to tell from the map, it appears drill stations are between 10 and 50 meters apart along the east-west lines—a good distance to establish grade and structural continuity.
I am afraid, however, that the drill data is too poorly organized and presented to permit any conclusion regarding grade continuity along strike and therefore the potential tonnes and grade of the proposed shoot, or continuity therein. Bayfield should present us with a series of north-south cross sections similar to Figure 2, indicating the thickness of the section (showing the distance holes are projected into the section), using all the drill holes with down-hole assays in order to prove BYV have discovered something of value. Many companies at this stage of outlining a possible resource do this on corebox.net or through their own websites. It’s basic exploration and disclosure practice in Canada.
When and if Bayfield does present the public with sufficient cross sections and maps to make an assessment of the grade and continuity of Burns Block and the postulated shoot, we are certain the US based newsletter writer will be happy to publicly review the data and, if need be, reconsider his current assessment of the company.
Are we clear now?
