CEO/Chief Geologist James A. Briscoe on x-ray fluorescence and in field procedures at Hay Mountain

May 28, 2016

Recently, an LBSR shareholder asked Liberty Star: “What is the SEC attitude toward public releases of field readings by Niton ahead of lab analysis of drill core?”

Jim answered this inquiry at length on Liberty Star’s message forum at, “the small cap epicenter.” Jim included his experience with x-ray fluorescence equipment and some of the planned procedures in the field at the Hay Mountain Project:

“The SEC and/or the Canadian National Instrument (NI) 43-101 regulations do not allow any assays not following their detailed protocols including handling and sample chain of custody regulations followed by Certified Assay Laboratory analysis  along with proper standards and cross checks to be used in order to determine values to be used in any calculation of mineral resources used in preparation of tonnage and grade calculations, that might lead up to a bankable feasibility study and declaration of ore reserves.  And thus we will state any results that are published which are certified assays. We have done a study of existing labs and their capabilities and have selected one which has the prerequisite sample preparation procedures, and assay procedures including QA/QC (Quality Assurance – Quality Control) procedures and a history of accurate and precise results.   And these values will be reported along with the Certified Laboratory ID when they have been completed.  As you might imagine, this will take some period of time – a matter of weeks or longer.

Any preliminary results released will be clearly stated as to what they represent, how samples were analyzed and any pertinent facts related to the drill core and sampling type and methodology.

However at the drill hole we will use other technology explained in various news releases.  If any of these results are released to the public it will be in the form of an official news release and state exactly what methodology was used and how it was done.  These technologies will allow the geologic team at the site to keep up what is being encountered in the drill hole and is no different than what has been ascertained from drill core or drill cuttings during the last 75 to 100 years, since efficient drilling methods were designed.  However we have much better tools available to us today.  These will be described in future news releases.

To give you more detail on my experience with X-Ray fluorescence please read the following brief history.

I first started working with X-Ray fluorescence with what was probably the originating company called SciTech which made the MAP or Metal Analysis Probe.  I was so impressed with the methodology that I went through a training course – essentially nuclear physics lite – which I also had in college.  The units were expensive and there was a resistance to “Black Boxes” at the time, and in addition a problem that came from an unexpected quarter.  In order to calibrate the 1995 vintage tool there had to be a series of accurately assayed samples running from trace metal to high grade metal, which came from the ore body where it was going to be used – (today’s units are self-calibrating) – and most of the mine assay offices had very poor quality control (assays) – which translated to very poor results in the MAP unit.  Finally I located one mine who had a superlative assayer – Tonopah Moly–. We calibrated their MAP unit and tested it in the open pit mine on blast hole cuttings at the collar of the blast holes.  It was pronounced as “accurate as the Company’s standard assays, by the company assayer.  As a result they purchased a MAP analyzer.  However, because there was too much opposition and too many challenges beyond my control I retired from MAP sales.

Today there are many XRF manufacturers and styles from all over the world. These generally use miniaturized X-Ray tubes rather than X-Ray emitting metal isotopes as in the first MAP units. Today’s units are much more accurate and precise for many more elements Also,  the results are faster with built-in  GPS units to record its location in 3-dimensional space, and a camera that looks through the X-Ray tube to record exactly what is being assayed. The results come back in 1/5th to 1/10th the time and are recorded in an internal computer for storage or transmission of results to a base computer.  Those results are significantly more accurate and precise, and growing more so each year.  The model we recently bought was state-of-the-art when we bought it, but a new model is now being tested that is smaller and with even more wonderful capabilities.

But please read these comments carefully.  And also read NR 193 where I describe the Solids Recovery Unit or SRU invented and manufactured by an Australian company.  It cleans the mud lubricant and flushing fluid (here you may want to Google “mud used in drilling” if you don’t know about it already) by collecting it as it comes out of the drill hole and spinning in a powerful centrifuge at 3,000 RPMs which separates the cuttings from the colloidal mud and pumps the 99.9% cleaned mud back down the hole where it makes the drilling go faster and cut down wear on the drill tools.  The cuttings are extruded where they can be bagged and properly disposed of.  But because the Driller knows what interval he drills from one point in time to another, the geologist can select the drilling interval and collect that sample, put some of the properly homogenized cuttings in a cup made for the Niton, and it can be assayed with the assay placed in a computer drill log so the geologist can know the mineral-metal content of the drill hole at that selected interval before that core ever comes out of the hole.  Thus an immediate assay log of the drill hole can be constructed.  This is exceedingly important information and has a direct bearing on a decision as to whether to stop the hole or continue, and a multitude of other decisions the geologic staff need to make in a timely basis.

The geologist always has the responsibility to make these critical and difficult decisions anyway but in past years he had to physically examine the core or cuttings with a hand lens and without the benefit of any assay data – which might come from the laboratory weeks of months later.  Instead he would have to guestimate whether the metal grade was going up (i.e. getting warmer) or down (i.e. getting colder) sometimes making the critical decision to stop a hole when it was actually getting better values with depth.

Then the core which is extracted from the drill hole and boxed in carefully designed core boxes, generally in 10 foot lengths, is then transported down to the core processing facility, under close control in sealed boxes.  The core will be then split using a diamond saw along its length.  One half is labeled and bagged in a canvas bag, while the other half remains in the archival box for permanent storage.  Then the formal assay process that you are asking about takes place.  And because we are close to Tucson where a Certified Assay Sample processing facility exists we will probably  take the split core samples there every 24 hours or so depending on a variety of factors.  We have picked this Certified Lab from a variety of possible choices because of their quality of sample preparation and all the things that go into it, which is one of the most important steps in the assay procedure.  Bad sample prep equals bad assays.  We relied on our Technical Director – Geochemist Shea Clark Smith to choose this assay facility.  After the samples have been  crushed and pulverized and prepared they are split scientifically into what are called “assay aliquots” and put into sealed paper bags made for the purpose and shipped by air to one of their assay facilities.  As these facilities are expensive to build, staff and maintain, they are established in a logistically convenient location.   They are highly mechanized and computerized and their dependability, reliability and accuracy and precision is ultimately what an exploration or mining company depends on for accurate determination of the metal content of each rock or core or soil or vegetation sample that is analyzed by them.  That is why the government regulators – Canadian or USSEC insists on use of Certified Labs. But even in these highly regulated labs errors can creep in for myriad of reasons.  That is why we have Geochemist Shea Clark Smith do continual checking on which labs and processes we should use and why there are continual checks and balances that we monitor.”

James A Briscoe, P. Geo AZ CA – LBSR CEO/Chief Geologist


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