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ORN Orsa Ventures Corp.

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Share Name Share Symbol Market Type
Orsa Ventures Corp. TSXV:ORN TSX Venture Common Stock
  Price Change % Change Share Price Bid Price Offer Price High Price Low Price Open Price Shares Traded Last Trade
  0.00 0.00% 0 -

Orsa Completes Review of Historic Metallurgical Testwork at Quartz Mountain

12/02/2013 4:19pm

Marketwired Canada


Orsa Ventures Corp. (TSX VENTURE:ORN) ("Orsa" or the "Company") is pleased to
announce that its consultants, JDS Energy and Mining Inc., have completed a
detailed review of metallurgical studies performed to date. The review confirms
that oxide mineralization responds well to cyanidation. Column leach testing
indicated recoveries between 74 to 88 percent on oxidized tuff and rhyolite. The
inferred oxide resource as reported in last year's NI 43-101 report (dated
February 2012) is shown in the table below:




---------------------------------------------------------------------------
                   Imperial Units                    Metric Units          
         ------------------------------------------------------------------
               Au                               Au                         
Area/      Cutoff     Tons     Au  Au Oz s  Cutoff   Tonnes     Au  Au Oz s
Material     (opt)    (000)  (opt) (000)(1)   (g/t)    (000)  (g/t) (000)(1)
---------------------------------------------------------------------------
Total                                                                      
 Oxide      0.006   70,710  0.018    1,297    0.21   64,148   0.63    1,297
---------------------------------------------------------------------------
Total                                                                      
 Sulfide    0.017   51,036  0.030    1,551    0.58   46,300   1.04    1,551
---------------------------------------------------------------------------
Total                                                                      
 Project      n/a  121,746  0.023    2,848     n/a  110,448   0.80    2,848
---------------------------------------------------------------------------



During the late 1980's metallurgical testing was done in support of
pre-feasibility and feasibility studies for the owner, Quartz Mountain Gold
Corporation ("QMGC"). The next and last major program was conducted by Pegasus
Gold Corporation in 1990 and 1991 in support of a two year pre-feasibility
study. All the metallurgical testing was performed by the Anaconda Research Lab
(1985); Kappes/Cassiday and Associates (1985); Bateman Labs (1986-1988); and
McClelland Labs (1988). Since 1991 no mineral processing and metallurgical
testing has been carried out on the project.


All samples collected for these programs were analyzed using bottle roll, test
columns, flotation tests, and bacterial oxidation tests to determine gold
recovery using cyanidation techniques. Given the deposit type (low grade bulk
tonnage), particular emphasis was placed on heap leach methods including cyanide
extraction bottle roll and column tests. 


In April 1988, Minproc (U.S.A.) Inc. completed a preliminary feasibility
analysis of the Crone Hill and Quartz Butte deposits. In May 1988, QMGC retained
Davy McKee Corporation to re-evaluate the metallurgical process and assay data.
Between mid-September and late November 1988, 19 deep drill holes totaling
14,675 feet were completed within the Quartz Butte deposit to explore for
high-grade feeder veins that could be located within the throat of the Quartz
Butte dome. 


From this drill program, ten larger samples were processed by bottle rolls and
column leach tests utilizing 3/4" and 1 1/2" crushed material. The results from
these tests led Davy McKee to the design of a split heap leach / milling flow
sheet whereby the lower grade oxides would be heap leached at a -3/4 inch crush
size and the higher grade oxides would be milled along with the sulfide ore. A
feasibility study was completed in August of 1989 with generally positive
conclusions.


Following the work conducted by Davy McKee, Pegasus became an active partner in
the property and immediately began a two year pre-feasibility study with a
well-defined metallurgical testwork program to confirm and potentially improve
upon a total heap leaching approach. While earlier testing was performed on both
drill hole cuttings and core samples, samples for Pegasus' test work program was
focused on:




--  Drill core from previous drilling to confirm claimed oxide heap leach
    results by rock type; 
--  Bulk samples taken by back hoe pits to represent low grade oxide
    mineralization for testing of run-of-mine heap leach kinetics, and; 
--  Drill core taken in a program specifically designed to represent sulfide
    mineralization in the various rock types throughout the ore body.



Oxide Results

Column testwork indicated that a crush size of minus 1/2 inch was determined to
be the optimum size for the four basic rock types that represented the deposit
for heap leaching. The expected gold recoveries by rock type are as follows:




--  Tuff - 77% 
--  Rhyolite - 74% 
--  Quartz Butte Rhyolite - 88% 
--  Basalt - 62%



Cyanide consumption was projected to average 0.75 lbs/ton ore while lime and
cement consumption combined to average 15 lbs/ton ore.


Sulfide Results

Tests on sulphide mineralization prior to Pegasus' involvement included cyanide
leaching at various particle sizes and preparative floatation testing. Gold
recoveries ranged from 15% for heap leach sized material up to 70% for selected
finely ground rock types. Flotation gold recoveries averaged 60-70% with
concentrate grades of 1-2 oz/t gold. 


After a detailed review of previous metallurgical testwork, Pegasus directed
their efforts to:




1.  Bacterial vat leaching of flotation concentrate coupled with cyanide
    leaching of flotation tails, and 
2.  Bacterial assisted heap leaching.



A core drilling program was completed to obtain representative sulfide samples
of all rock types from all areas of the ore body. Bench scale results of
flotation followed by agitated cyanide leaching recovered 57% of the gold while
bacterial oxidation of the flotation concentrate followed by agitated cyanide
leaching recovered 75% of the gold. Ultimately Pegasus projected a gold recovery
of 70% for bacterially oxidized heap leach sulfides.


Follow up testwork

Additional drilling and testwork has been recommended to support both the heap
leaching of oxide mineralization and processing of sulphide mineralization.
Phase one would focus on the oxide mineralization. In support of that testwork,
Orsa has relogged and assayed 5,000 metres of drill core from a 2004 drill
program (see news release dated January 16, 2013) and is permitting a drill
program for the spring of 2013 for confirmation drilling and metallurgical
samples. Follow on bottle roll and column testing will be conducted at various
crush sizes on oxide mineralization.


It is the opinion of Orsa's consultant's that sulphide mineralization may be
economically recovered by milling and cyanidation. Testwork to refine a process
would include testing for crush and grind size, mineralogy, flotation, leaching,
and settling and filtration. 


Matt Bender, QP, P.E., Director of Metallurgy for JDS Energy and Mining Inc.,
has reviewed the contents of this news release and is a Qualified Person as
defined by National Instrument 43-101.


About Orsa

Orsa Ventures Corp. is a junior company focused on the exploration for, and
development of, gold-silver-copper properties in the western United States. In
addition to its Quartz Mountain Property, Orsa recently announced the discovery
of significant sediment-hosted gold system at its Coal Canyon Property in the
Oreana Mining Trend, Nevada, where over 10 million ounces has been discovered
since 2009. The Company also has the right to earn a 51% interest Ashby
Property, a former gold producer and porphyry copper-gold target, located in the
Walker Lane Mining Trend, host to several large copper and gold deposits in
Nevada.


On behalf of the Board of Directors,

Linda Thorstad, President and Chief Executive Officer

FORWARD LOOKING STATEMENTS

This news release contains forward-looking statements that are based on the
Company's current expectations and estimates. Forward-looking statements are
frequently characterized by words such as "plan", "expect", "project", "intend",
"believe", "anticipate", "estimate", "suggest", "indicate" and other similar
words or statements that certain events or conditions "may" or "will" occur, and
include, without limitation, statements regarding the Company's plans with
respect to the closing of the Financing and the use of proceeds thereof. Such
forward-looking statements involve known and unknown risks, uncertainties and
other factors that could cause actual events or results to differ materially
from estimated or anticipated events or results implied or expressed in such
forward-looking statements. Any forward-looking statement speaks only as of the
date on which it is made and, except as may be required by applicable securities
laws, the Company disclaims any intent or obligation to update any
forward-looking statement, whether as a result of new information, future events
or results or otherwise. Forward-looking statements are not guarantees of future
performance and accordingly undue reliance should not be put on such statements
due to the inherent uncertainty therein.



FOR FURTHER INFORMATION PLEASE CONTACT: 
Orsa Ventures Corp.
Linda Thorstad
President and Chief Executive Officer
604.608.6680
604.558.0087 (FAX)
www.orsaventures.com

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