fyi, 16 July 1999
Attention Business Editors:
Birch Mountain Reports Technical Overview and Analytical Results for Athabasca PGM-GOLD Project
CALGARY, July 16 /CNW/ - Birch Mountain Resources Ltd. (BMD:ASE) wishes
to provide a technical overview of the results of assay and analytical method
development work carried out by Birch Mountain and others on its Prairie Gold
properties. Analytical data have been generated by or on behalf of Birch
Mountain, and independently by other companies, government agencies and
universities.
Summary
-------
Birch Mountain concludes that the results of analyses of drill core and
surface samples highlighted below, conclusively prove the existence of
anomalous quantities of gold, silver, platinum, palladium and other precious
and base metals in rocks from our Athabasca property. Testing of quantitative
assay methods developed by Birch Mountain and other parties, however, has not
yet achieved our objective of developing a method for repeatable,
statistically sound estimates of precious metal concentrations. Recent
advances in our understanding of the underlying chemical systems related to
mineral genesis, have enabled Birch Mountain to achieve intermittent detection
of important levels of gold, platinum and palladium. We feel that the
variability in results is related to control of certain process parameters
that are now systematically being tested. We know that gold, platinum,
palladium and other precious and base metals are present in our Athabasca
rocks, but at this point we can not quantify their concentrations within
acceptable statistical variance.
Electron Imaging
----------------
As stated in the news release of June 24, 1999, Birch Mountain considers
that scanning electron microscope (SEM) and electron microprobe (EMP) data
conclusively prove the existence of anomalous quantities of gold, silver,
platinum, palladium and other precious and base metals in sedimentary rocks
from Athabasca. Birch Mountain, the Geological Survey of Canada, Lac Minerals
and others have conducted extensive SEM/EMP imaging and elemental analyses of
surface samples and drill core from Athabasca using secondary and
backscattered electron (BSE) imaging, and energy and wavelength dispersive
x-ray spectrometry. Over 200 distinct chemical species comprising native and
multi-element precious metal particles, and more widely distributed base metal
particles, notably Cu, Zn and Pb, have been documented. As an example, one
broken surface on one drill core specimen examined by SEM/EMP contained 90
micron-sized gold-bearing particles. The existence of placer accumulations of
distinctive flour gold in rivers and streams in Athabasca further supports a
local source of gold and other precious metals. Sources of information for
SEM/EMP results are listed in Table 1.
Table 1. Precious metals detected by SEM and EMP analysis, Athabasca and
Dawson Bay.
<<
Laboratory Area Precious Metals
------------------------------------------------------------------------
Geological Survey of Canada (GSC), Athabasca Au, Ag, Pt, Pd, Ir
Calgary, AB -------------------------------
Dawson Bay Au, Ag
------------------------------------------------------------------------
GSC, Ottawa, ON Athabasca Au, Ag, Pt,
placer Au
------------------------------------------------------------------------
Lac Minerals Limited, Denver, CO Athabasca Au, Ag
------------------------------------------------------------------------
Canmet, Ottawa, ON Athabasca Au
------------------------------------------------------------------------
Cannon Microprobe, Seattle, WA Athabasca Au, Ag, Re
------------------------------------------------------------------------
Amtel, London, ON Athabasca Au, Ag
------------------------------------------------------------------------
Durban University, South Africa Athabasca Au, Ag, Pd, Os
------------------------------------------------------------------------
Alberta Geological Survey, Edmonton, AB Athabasca Au
------------------------------------------------------------------------
U. Alberta; L. Giusti M.Sc. thesis Athabasca Placer Au
------------------------------------------------------------------------
U. Calgary; B. Tsang, M.Sc. thesis Athabasca Pt, Ag
------------------------------------------------------------------------
U. Manitoba; S.M. Ramnath, M.Sc. thesis Dawson Bay Au, Ag, Pd
------------------------------------------------------------------------
>>
The SEM/EMP data show that the gold particle size population, determined
from measurements of 170 particles, exhibits a truncated distribution with
nearly 50% of measured gold particles falling in the smallest size range of
less than 2 microns. SEM/EMP imaging also shows that micron sized gold
particles commonly are surrounded by a large number of sub-micron sized gold
particles. From these data we conclude that the majority of precious metal
particles lie in the sub-micron size range.
Previous Analytical Results
---------------------------
Since 1994, Birch Mountain and others have tested established methods for
the assay and analysis of precious metals in sedimentary rocks from Athabasca.
In contrast to SEM/EMP imaging and microanalysis, which prove the existence of
precious metals in these rocks in amounts well above lower limits of
detection, conventional analytical results have been inconclusive, either
because they fail to detect precious metals or because positive results can
not be repeated routinely. A small proportion of such analyses have reported
precious metals. These include:
- 4.1 g/t gold measured by Aztec K x-ray analysis at Anglo American
Research Laboratories, Johannesburg, South Africa, for a composite
sample prepared from 7 drill core grab samples collected between 159.1
and 185.3 metres depth in Lac drill hole ATH94-01;
- An average grade of 0.36 g/t gold over a 5.0 m interval from 148.5 to
153.5 metres depth in Lac drill hole ATH94-04 measured by fire
assay-ICP at Anglo American Research Laboratories;
- 1.69 g/t gold measured by fire assay of activated carbon used to
extract gold from a cyanide bottle roll leach of a 150 g sample of
surface rock at Saskatchewan Research Council, Saskatoon, Saskatchewan.
Neither the Aztec nor the cyanide leach results could be reproduced by
alternate methods. It is unlikely that the lack of repeatability can be
explained by inadequate sampling or by the ``nugget effect'' because of the
inferred predominance of sub-micron precious metal particles.
1998 Bulk Samples
-----------------
In 1998 Birch Mountain prepared four bulk samples of visibly altered
sedimentary rocks to provide the samples to approach this problem
systematically. Details of each of the four bulk samples are given in Table
2. The bulk samples were submitted to Loring Laboratories Ltd., Calgary,
Alberta, for (a) crushing to -0.25 inch using a jaw crusher, and (b)
pulverizing to -100 mesh using a disc pulverizer.
Table 2. Bulk samples, Athabasca, 1998.
<<
Sample Location Type Size Length Formation Member Description
-------------------------------------------------------------------------
BJ98-008 Trench Channel 50 Kg 1.5 m Waterways Moberly Altered
limestone
-------------------------------------------------------------------------
BJ98-009 Trench Channel 50 Kg 1.5 m Waterways Moberly Altered
limestone
-------------------------------------------------------------------------
HAR98-001 Trench Bulk 50 Kg - Waterways Moberly Sideritized
limestone
-------------------------------------------------------------------------
HAR98-002 Trench Bulk 50 Kg - Waterways Moberly Decarbonated
limestone
-------------------------------------------------------------------------
>>
The four bulk samples were submitted to ITS Bondar Clegg, North
Vancouver, B.C., for standard fire assay and multi-element ICP analysis.
Results for precious metals are shown in Table 3; neutron activation results
for sample BJ98-008 are given in Table 4. The data clearly show that standard
fire assay and instrumental neutron activation analyses of the 1998 bulk
samples detect negligible concentrations of precious metals in these samples.
Table 3. Lead collector fire assay results for 1998 bulk samples; ITS
Bondar Clegg.
<<
Sample Au (g/t)(1) Pt (g/t)(1) Pd (g/t)(1) Ag (g/t)(2)
-------------------------------------------------------------------------
BJ98-008 0.003 less than 0.005 0.003 1.4
-------------------------------------------------------------------------
BJ98-009 0.002 less than 0.005 0.002 2.1
-------------------------------------------------------------------------
HAR98-001 0.002 less than 0.005 0.002 0.5
-------------------------------------------------------------------------
HAR98-002 0.002 less than 0.005 0.002 less than
0.5
-------------------------------------------------------------------------
>>
(1) Fire assay/ICP; ITS Bondar Clegg, method code FA-56.
(2) HF-HNO3-HCIO4-HCI digest/ICP; ITS Bondar Clegg.
Table 4. Instrumental neutron activation analysis, ITS Bondar Clegg
<<
Sample Au (g/t) Ir (g/t) Ag (g/t)
----------------------------------------------------
BJ98-008 less than less than less than
0.002 0.050 2
----------------------------------------------------
>>
The four 1998 bulk samples were also provided to International
Metallurgical and Environmental of Kelowna, B.C., through EnviroGold
Technologies Inc., of Calgary, Alberta. Aqua regia digestion followed by AA
determination of precious metals yielded nil results with the exception of
sample BJ98-008 which reported 0.08 g/t gold and 11 g/t platinum.
Analytical Method Development
-----------------------------
In March, 1999, Birch Mountain initiated an in-house program to develop
analytical methods to resolve inconsistencies between SEM/EMP imaging and
precious metals analysis, and to address the problem of repeatability. By
adjusting experimental conditions, by carefully recording experimental
conditions, and by systematically varying key parameters, Birch Mountain is
deliberately striving to identify and control the variables causing the
erratic results. We are using Birch Mountain's laboratory, and facilities and
analytical instrumentation available in the Department of Geology at the
University of Calgary. Significant results from Birch Mountain's recent
in-house work are given in Table 5. Atomic absorption measurements carried
out by Birch Mountain at the University of Calgary utilized three point
standard additions calibration and deuterium arc background correction.
Table 5. Summary of Birch Mountain in-house analytical method
development
results, 1998 bulk sample BJ98-008.
<<
Digest Extraction Collector Analysis Type Au (g/t) Pt (g/t) Pd (g/t)
-------------------------------------------------------------------------
Reductive Static None FA/ICP(3) 0.593 0.132 0.015
-------------------------------------------------------------------------
Caustic Bottle roll Adsorption FA/ICP 0.008 0.002 1.01
-------------------------------------------------------------------------
Acidic Bottle roll Adsorption FA/ICP 0.008 0.004 1.90
-------------------------------------------------------------------------
Caustic Bottle roll Adsorption FA/ICP 0.009 nd 0.558
-------------------------------------------------------------------------
Acidic Static Chiddey FA/ICP 0.0008 nd 0.427
-------------------------------------------------------------------------
Acidic Static None AA(4) 4 to 6 na na
-------------------------------------------------------------------------
>>
(3) Fire assay - ICP; Loring Laboratories Ltd., Calgary, AB.
(4) Atomic absorption, University of Calgary, Calgary, AB.
na - not analyzed; nd - not detected
Although Birch Mountain's testing has shown important values of gold and
palladium, we have not yet been able to reproduce ``hits'' despite careful
attention to replicating the conditions and procedures of runs which yielded
positive results. We can not yet explain this lack of repeatability. It is
unlikely, however, that contamination is responsible because we obtain similar
results using different methods and laboratories. Results for sample BJ98-008
are summarized in Table 6.
Table 6. Summary of assay and leach results, 1998 bulk sample BJ98-008.
<<
Method Laboratory Au (g/t) Ag (g/t) Pt (g/t) Pd (g/t)
-------------------------------------------------------------------------
FA/ICP Bondar Clegg 0.003 1.4 less than 0.005 0.003
-------------------------------------------------------------------------
INAA Bondar Clegg less than less than
0.002 2 na na
-------------------------------------------------------------------------
Aqua I M and E 0.08 na 11 nd
regia
digest/AA
-------------------------------------------------------------------------
Aqua Birch / 4 to 6 na na na
regia U of Calg.
digest/AA
-------------------------------------------------------------------------
Reductive Birch Mountain/ 0.593 na 0.132 0.015
pre-treatment, Loring
FA/ICP
-------------------------------------------------------------------------
Bottle roll, Birch Mountain/ 0.008 to na 0.002 to 0.558 to
column Loring 0.009 0.004 1.90
adsorption,
FA/ICP
-------------------------------------------------------------------------
Aqua regia Birch Mountain/ 0.0008 na nd 0.427
digest, Loring
Chiddey
precip,
FA/ICP
-------------------------------------------------------------------------
>>
The foregoing analytical results convince Birch Mountain that:
- precious metals are present in anomalous quantities in rocks from
Athabasca;
- standard analytical protocols are unable to accurately determine the
concentrations of precious metals in these rocks;
- processes currently being tested by Birch Mountain provide
intermittent indications of quantities of precious metals but do not
repeat with an acceptable frequency;
- our understanding of the underlying chemistry of these mineralized
systems enables progress in improving predictive analytical protocols.
FORWARD-LOOKING STATEMENTS: This news release contains certain forward-
looking statements. All statements, other than statements of historical fact,
included herein, including without limitation, statements regarding potential
mineralization and reserves, exploration results and future plans and
objectives of Birch Mountain Resources Ltd. (``Birch Mountain'') are
forward-looking statements that involve various risks and uncertainties. There
can be no assurance that such statements will prove to be accurate and actual
results and future events could differ materially from those anticipated in
such statements. Important factors that could cause actual results to differ
materially from Birch Mountain's expectations are disclosed elsewhere in Birch
Mountain's documents filed from time to time with the Alberta Stock Exchange
and other regulatory authorities. Forward-looking statements are based on the
estimates and opinions of management on the date the statements are made, and
Birch Mountain does not undertake any obligation to update forward-looking
statements should conditions or management's estimates or opinions change.
The Alberta Stock Exchange has neither approved nor disapproved the
information contained herein.
%SEDAR: 00003909E
-30-
For further information: Doug Rowe, President and CEO or Jane Quinn,
Shareholder Services, Birch Mountain Resources Ltd., Tel: (403) 262-1838, Fax:
(403) 263-9888, Email: rowed@birchmountain.com,
jquinn@birchmountain.com, Home page: birchmountain.com
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