DENVER, July 24, 2017 /CNW/ -- Vista Gold Corp. (the
"Company," "we" or "our") (NYSE MKT: VGZ) (TSX: VGZ) today
announced the completion of the automated sorting tests on the
coarse fractions of the four 5-tonne bulk samples from its Mt Todd
gold project. The tests, completed at the facilities of Tomra
Sorting Solutions near Hamburg,
Germany, demonstrate that plus 5/8" (16 mm) product from the
HPGR crusher can be efficiently sorted to separate the
non-gold-bearing particles from the gold-bearing sulfides and
quartz/calcite veining, at production rates.
The tests confirmed that, consistent with previous test work,
8-10% of the run-of-mine feed to the crushing circuit can be
removed from the process stream prior to the grinding
circuit. This is expected to reduce grinding circuit
operating costs and provide a modest increase in grade to the
grinding circuit. These results, combined with the favorable
previously announced results of the HPGR crushing tests, provide
support for key assumptions underlying the Company's decision to
commence an update of the Mt Todd Preliminary Feasibility Study
("PFS").
Vista's President & CEO, Frederick
H. Earnest, commented, "The application of this technology
is not new to the mining sector and it is being used effectively
where ores have distinct visual and/or density variations. Being
present for the automated sorting of the bulk samples at production
rates allowed us to observe the efficiency of this technology and
its applicability to the Mt Todd gold project. The material
balance results are consistent with previous test results and we
expect to have assay results for the sorted material in August.
"With this phase of our metallurgical testing program complete,
we are prepared to commence the grinding and leach recovery
optimization testing once the samples are returned from
Germany. The final results of this
metallurgical testing program are expected to be available the
middle of September. We have commenced the work of updating our PFS
for the Mt Todd gold project, inclusive of flow sheet changes to
integrate this sorting technology. We believe these changes
will deliver a better technical project with improved
economics."
Automated Sorting Test Results
The bulk sorting tests confirmed our ability to selectively
remove particles known to have minerals associated with the
presence of gold in the Batman deposit at production rates.
The plus 5/8" (16 mm) material from the HPGR crushing/screening
tests at Thyssen Krupp Industries was shipped to the facilities of
Tomra Sorting Solutions. Three members of Vista's
management/project development team were present to observe the
tests, which were conducted in a standard production-size sorter
with a 60 cm wide belt. Material from each of the four
composites was sorted first using x-ray transmission ("XRT") to
remove particles containing sulfide minerals and subsequently using
lasers to remove particles containing quartz/calcite. The XRT
sorting tests were conducted at three different sensitivity
levels. The material balance results of the
sorting tests are summarized in the following table.
Plus 5/8"
Fraction
|
Composite
1
|
Composite
2
|
Composite
3
|
Composite
4
|
XRT
Sorted Material
|
33-57%
|
38-54%
|
27-46%
|
38-57%
|
Laser
Sorted Material
|
2.2-1.4%
|
7.6-6.7%
|
7.7-5.1%
|
1.9-1.3%
|
Sorting
Reject
|
40-62%
|
38-54%
|
46-64%
|
40-59%
|
Fraction of Total
Composite
|
|
Sorting
Reject
|
7.0-10.9%
|
6.8-9.6%
|
7.7-10.7%
|
7.4-11.0%
|
Each composite represents a different part of the Batman deposit
with varying amounts of sulfide and quartz/calcite mineralization
which provided the opportunity to sort material that represented:
high grade core, low grade peripheral, average to high grade early
production and average grade main deposit. The variation in
the amount of material sorted by the XRT and laser sorting steps is
a reflection of the relative mineral content and is not an
indication of sorting efficiency. Upon receipt of assay
results, the Company will determine the optimal settings, taking
into consideration gold losses, grade of sorted product and total
product rejected.
Based on the results of this testing, the Company plans to apply
a different sorting recovery/waste reject factor to each of the
different major mineralization styles in the deposit.
Commencement of Preliminary Feasibility Study Update
We believe that the Mt Todd gold project is a better gold
project today as a result of the project optimization work
completed over the last 12 months and we have commenced the work of
updating the current PFS. As part of this work we intend to
evaluate and include all appropriate production improvements and
the most current economic factors. We believe the results of
this study, when completed late this year or early next year, will
demonstrate a technically improved project and provide an improved
perspective of the value of the Mt Todd gold project at present
gold prices.
Qualified Person
The scientific and technical information disclosed in this press
release has been reviewed and approved by Mr. John Rozelle, Senior Vice President of Vista and
a qualified person (as defined by Canadian National Instrument
43-101).
About Vista Gold Corp.
The Company is a well-funded gold project developer. Our
principal asset is our flagship Mt Todd gold project in Northern
Territory, Australia. Mt Todd is one of the largest
undeveloped gold projects in Australia. For more information about our
projects, including technical studies and resource estimates,
please visit our website at www.vistagold.com.
For further information, please contact Connie Martinez at (720) 981-1185.
Forward Looking Statements
This press release contains forward-looking statements within
the meaning of the U.S. Securities Act of 1933, as amended, and
U.S. Securities Exchange Act of 1934, as amended, and
forward-looking information within the meaning of Canadian
securities laws. All statements, other than statements of
historical facts, included in this press release that address
activities, events or developments that we expect or anticipate
will or may occur in the future, including such things as our
belief that plus 5/8" product from the HPGR crusher can be
efficiently sorted at production rates (including the ability to
selectively remove minerals associated with the presence of gold at
the Batman deposit); our expectation that the removal of 8-10% of
the run-of-mine feed to the crushing circuit from the process
stream prior to the grinding circuit will reduce operating costs
and provide a modest increase in the grade to the grinding circuit;
our plans to commence grinding and leach recovery optimization
testing; the expected timing of, the completion of and the expected
results of our proposed metallurgical testing program, assay
results and updated PFS; and our belief that the Mt Todd gold
project is a better technical project with improved economics; and
other such matters are forward-looking statements and
forward-looking information. The material factors and assumptions
used to develop the forward-looking statements and forward-looking
information contained in this press release include the following:
our approved business plans, exploration and assay results, results
of our test work for process area improvements, mineral resource
and reserve estimates and results of preliminary economic
assessments, prefeasibility studies and feasibility studies on our
projects, our experience with regulators, representative samples
reflect the Mt Todd gold project, and positive changes to current
economic conditions and the price of gold. When used in this
press release, the words "optimistic," "potential," "indicate,"
"expect," "intend," "hopes," "believe," "may," "will," "if,"
"anticipate," and similar expressions are intended to identify
forward-looking statements and forward-looking information.
These statements involve known and unknown risks, uncertainties and
other factors which may cause the actual results, performance or
achievements of the Company to be materially different from any
future results, performance or achievements expressed or implied by
such statements. Such factors include, among others,
uncertainty of resource and reserve estimates, uncertainty as to
the Company's future operating costs and ability to raise capital;
risks relating to cost increases for capital and operating costs;
risks of shortages and fluctuating costs of equipment or supplies;
risks relating to fluctuations in the price of gold; the inherently
hazardous nature of mining-related activities; potential effects on
our operations of environmental regulations in the countries in
which it operates; risks due to legal proceedings; risks relating
to political and economic instability in certain countries in which
it operates; uncertainty as to the results of bulk metallurgical
test work; and uncertainty as to completion of critical milestones
for Mt Todd; as well as those factors discussed under the headings
"Note Regarding Forward-Looking Statements" and "Risk Factors" in
the Company's latest Annual Report on Form 10-K as filed on
February 22, 2017 and other documents
filed with the U.S. Securities and Exchange Commission and Canadian
securities regulatory authorities. Although we have attempted
to identify important factors that could cause actual results to
differ materially from those described in forward-looking
statements and forward-looking information, there may be other
factors that cause results not to be as anticipated, estimated or
intended. Except as required by law, we assume no obligation
to publicly update any forward-looking statements or
forward-looking information; whether as a result of new
information, future events or otherwise.
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SOURCE Vista Gold Corp.