Barkerville Provides Update – Screen Metallic Fire Assays
Vancouver, BC - Barkerville Gold Mines Ltd. ("Barkerville" or the "Company") is pleased to provide an update on its Screen Metallic Fire Assay Program for its Gold Quartz (Cow Mountain) prospect, part of the Cariboo Gold Project, near Wells, British Columbia. The Company continues the implementation of recommendations put forward in the Cow Mountain Technical Report, dated December 31, 2012 (the "Technical Report", see News Release dated June 19 2013).
Gold Quartz Mine/Cow Mountain
APEX Geoscience Ltd. (APEX), geological consultants to the Company, has completed a preliminary review of data resulting from the Cow Mountain Double Assay program. To date, a total of 2,056 core samples have yielded a 20.9% increase in the mean (average) Screen Metallic Fire Assays ("Metallic FA") grade as well as a 16.0% increase in the mean length-weighted Metallic FA grade versus the corresponding original standard 30 gram Fire Assay ("FA"). The Double Assay program was initiated in 2012 by Snowden Mining Industry Consultants Inc. as part of its efforts related to the completion of the Technical Report in order to evaluate the effectiveness of the Company's assay procedures with respect to the measurement of coarse gold. The program comprised the completion of 500 gram Screen Metallic Fire Assays (Metallic FA) on coarse reject material remaining from samples that were initially assayed by a standard 30 gram FA with an Atomic Absorption (AA) or gravimetric finish. A total of 2,056 samples were re-assayed as part of the program that were collected from a total of 10 diamond drill holes completed in 2011 and 14 diamond drill holes completed in 2012.
In conducting its review of the 'Double Assay' dataset, APEX has performed a preliminary statistical review of the analytical results for the actual drill core samples as well as a preliminary review of the QAQC data resulting from Company inserted and Laboratory inserted standards, blanks and duplicates. No significant issues were identified within the QAQC data and thus it was concluded that assay variation is primarily a result of coarse gold and the resulting "nugget effect".
The Table provided below summarizes basic comparative statistics for the Double Assay dataset. An examination of simple arithmetic mean values for the two assay techniques indicates an apparent 20.9% increase in the mean Metallic FA value relative to the mean standard FA value. Similarly, there is an apparent 16.0% increase in the mean length-weighted Metallic FA value relative to the mean length-weighted standard FA value. A detailed review of the data indicates that the mean values discussed above are strongly influenced by a relatively small number of high grade assay results. Furthermore, an examination of assay frequency distribution data and mean assay values over different grade intervals identified portions of the data that expressed little or no statistical difference between the two assay techniques. However, the median values for the two sets of analyses also show an apparent increase in the Metallic FA results relative to the standard FA results. The median value for the raw (un-weighted) assay data increases 17.6% for the Metallic FA technique and 11.1% for length-weighted data. This combination of increased mean and median values is strongly indicative of a real difference between the two data populations and thus an overall increase in the Metallic FA results relative to the initial standard FA results. This conclusion is further supported by detailed Log Probability and Q-Q plot analysis of the data along with a detailed review of the data in different grade ranges.
Table 1: Summary Statistics Screen Metallic FA vs Standard FA.
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| | |FA |Metallic FA|%Diff |
|-----------------------------------------------|
|Raw Assay Data (n = 2,056) |
|-----------------------------------------------|
| |Min |0.0025 |0.005 | |
|-----------------------------------------------|
| |Max |821 |925.09 | |
|-----------------------------------------------|
| |Mean |1.71 |2.06 |20.9% |
|-----------------------------------------------|
| |Median |0.017 |0.020 |17.6% |
|-----------------------------------------------|
| |Std. Dev |19.96 |24.12 | |
|-----------------------------------------------|
| |Coeff.Var.|11.70 |11.69 | |
|-----------------------------------------------|
| Length Weighted Data (n = 2,056) |
|-----------------------------------------------|
| |Min |0.00004 |0.00008 | |
|-----------------------------------------------|
| |Max |848.02 |955.54 | |
|-----------------------------------------------|
| |Mean |1.07 |1.24 |16.0% |
|-----------------------------------------------|
| |Median |0.018 |0.020 |11.1% |
|-----------------------------------------------|
| |Std. Dev |19.21 |22.03 | |
|-----------------------------------------------|
| |Coeff.Var.|17.91 |17.70 | |
|-----------------------------------------------|
| |Length (average) |6.10 ft | |
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Although a difference between the Metallic and standard FA data sets can be shown statistically, the overall increase in the Metallic FA results, relative to the standard FA results, is difficult to quantify in detail. This is the result of significant variance (as an example see the high Coefficient of Variation data in Table 1) within and between the two datasets that is attributable to the presence of coarse gold within many of the samples (See news release dated August 20, 2013). Thus, although the results of the Double Assay program completed to date are encouraging and suggest that the original standard FA technique has, in a number of cases, understated the gold grades, the Company reiterates the cautionary statement that the apparent increase in Metallic FA results relative to the initial standard FA results, from the limited number of samples analyzed thus far, cannot be extrapolated with any certainty to the entire Cow Mountain drill assay database.
The difference between the two assay techniques is aliquot size. The standard FA technique was conducted on a relatively small (30 gram) aliquot of sample material that may or may not be truly representative of the gold content of the sample as a whole, particularly if coarse gold is present that is notoriously difficult to homogenize within a sample pulp. The Screen Metallic technique utilized in the Company's Double Assay Program effectively evaluates 500 grams of pulverized material for each sample and was specifically developed by laboratories to measure coarse gold within pulverized sample materials to provide a more representative estimate of overall gold content. In consideration of the results of the Double Assay Program, the Company has committed to conducting larger aliquot gold assays for the analysis of all future drill core and surface trench/channel samples, as well as for the significant Infill Assay Program that is currently underway, as per one of the recommendations within the NI 43-101 Technical Report dated December 31, 2012.
A significant number of additional samples are currently being assayed by Metallic FA, which will further increase the quality of the Cow Mountain assay database. Once all of this data has been received and verified, the Cow Mountain assay database will be updated and, if appropriate, the Cow Mountain resource will be updated and any material changes will be reported.
The information contained in this news release has been reviewed and approved by the Company's Chief Geologist Jim Yin, Ph.D., P. Geo. and Mr. Michael Dufresne, M. Sc., P. Geo. of APEX, an independent consultant, both of whom are Qualified Persons as defined by National Instrument 43-101 Standards of Disclosure for Mineral Projects.
"J. Frank Callaghan"
J. Frank Callaghan
President and CEO
About Barkerville Gold Mines Ltd.
Since the mid-1990s the Company has focused on exploration and development of gold projects in the Cariboo Mining District in central B.C. The Company's mineral tenures cover 1,164 km2 along a strike length of 60 km and approximate width of 20 km, including the fully permitted Bonanza Ledge Gold Mine, the Gold Quartz prospect on Cow Mountain, and Barkerville and Island Mountain exploration targets in addition to seven past producing hard rock mines. The QR Property was acquired in February 2010 and includes a 900 tonne/day gold milling facility and a permitted gold mine located approximately 110 km by highway and all-weather road from the Barkerville Gold Camp. The Company began pouring dore gold in September 2010, continued until December 2011, and resumed for 2 months in January and February 2013. In November 2010, the Company acquired a second permitted mill and property, the 1360 tonne/day Goldstream Mine currently on care and maintenance in Revelstoke, B.C. The Company has completed significant drilling and exploration programs and, together with the historical data, is compiling all information to determine the geologic models and updated technical reports to continue with exploration and development of the Cariboo Gold projects. This news release has been prepared on behalf of the Board of Directors of the Company which takes full responsibility for its contents.
Cautionary Statement on Forward-Looking Information
Certain information in this news release is forward-looking within the meaning of certain securities laws, and is subject to important risks, uncertainties and assumptions. This forward-looking information includes, among other things, information with respect to the Company's beliefs, plans, expectations, anticipations, estimates and intentions, including the listing and trading of the Company's common shares on the TSXV. The words "may", "could", "should", "would", "suspect", "outlook", "believe", "anticipate", "estimate", "expect", "intend", "plan", "target" and similar words and expressions are used to identify forward-looking information. The forward-looking information in this news release describes the Company's expectations as of the date of this news release.
The results or events anticipated or predicted in such forward-looking information may differ materially from actual results or events. Material factors which could cause actual results or events to differ materially from such forward- looking information include, among others, the Company's ability to engage and retain qualified key personnel, employees and affiliates, to obtain capital and credit and to protect its property rights.
The Company cautions that the foregoing list of material factors is not exhaustive. When relying on the Company's forward-looking information to make decisions, investors and others should carefully consider the foregoing factors and other uncertainties and potential events. The Company has assumed a certain progression, which may not be realized. It has also assumed that the material factors referred to in the previous paragraph will not cause such forward-looking information to differ materially from actual results or events. However, the list of these factors is not exhaustive and is subject to change and there can be no assurance that such assumptions will reflect the actual outcome of such items or factors.
THE FORWARD-LOOKING INFORMATION CONTAINED IN THIS NEWS RELEASE REPRESENTS THE EXPECTATIONS OF THE COMPANY AS OF THE DATE OF THIS NEWS RELEASE AND, ACCORDINGLY, IS SUBJECT TO CHANGE AFTER SUCH DATE. READERS SHOULD NOT PLACE UNDUE IMPORTANCE ON FORWARD-LOOKING INFORMATION AND SHOULD NOT RELY UPON THIS INFORMATION AS OF ANY OTHER DATE. WHILE THE COMPANY MAY ELECT TO, IT DOES NOT UNDERTAKE TO UPDATE THIS INFORMATION AT ANY PARTICULAR TIME.
Neither the TSXV nor its Regulation Services Provider (as that term is defined in the policies of the TSXV) accepts responsibility for the adequacy or accuracy of this news release.
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