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Kaminak Reports Over 90% Gold Recovery from 23 of 26 Column Leach Tests on Coffee Oxide Material at Various Crush Sizes‏

May 4, 2015

Vancouver, B.C. - Kaminak Gold Corporation (KAM: TSX-V) today announced results of the comprehensive metallurgical test work program at the Coffee Gold Project, Yukon, that will provide process input data for the Feasibility Study scheduled for completion in early 2016. The primary objectives of the metallurgical program were to confirm the previous excellent metallurgical test results, expand the testing to all currently known potential mine areas identified, and determine optimal gold recoveries and crush sizes for the Feasibility Study.

Highlights from this work include:

  • Column leach gold recoveries for bulk surface trench oxide samples for the Latte Deposit 6” crushed material averaged 88.5% (2 tests) and for the Supremo Deposit 6” crushed material averaged 87% (2 tests).  
  • Column leach gold recoveries for bulk surface trench oxide samples for Latte 2” and Latte ½” crushed material averaged 93.5% (4 tests), and for Supremo 2” and Supremo ½” crushed material averaged 94.5% (4 tests), with very little difference between the 2” and ½’ crush sizes.
  • Column leach gold recoveries for oxide core composites for Latte 2” and Latte ½” crushed material averaged 94.2% (4 tests), and for Supremo 2” and Supremo ½” crushed material averaged 94.0% (4 tests), again with very little difference between the 2” and ½’ crush sizes.
  • Column leach gold recoveries for oxide core composites for the Double Double Deposit 2” and Double Double ½” crushed material averaged 95% (2 tests), and for the Kona Deposit 2” and Kona ½” crushed material averaged 89.5% (2 tests).
  • Agglomeration was not required for any of the column tests and low reagent consumption was reported.
  • All of the column leach tests at the 0.5 inch size were performed at a temperature of 4 degrees Centigrade to simulate cold climate leaching. Column leach test work was conducted by Kappes, Cassiday and Associates, industry leading experts in heap leach processing.
Fred Lightner, Kaminak Director of Mine Development, stated: “This latest round of metallurgical test work strongly confirms previous testing. The volume of test work now completed on oxide has consistently produced high gold recoveries demonstrating the remarkable amenability of the Coffee deposits to the heap leach process. Crush size and recoveries from all facies, including oxide, upper and mid transitional materials, will be further evaluated in conjunction with the results of the 2015 infill drilling and the updated block models. This analysis will then determine the final decision around crush size to be incorporated into the feasibility study due out in early 2016.”  

2014-2015 Coffee Gold Project Metallurgical Test Work Program
Results of the column leach tests conducted by Kappes, Cassiday and Associates (“KCA”) are detailed below in Table 1 and 2. It should be noted that 3 different crush sizes were tested on the bulk samples: 6” refers to a sample 100% passing 175 mm or approximately 80% passing 150 mm, 2” refers to a sample 100% passing 62.5 mm or approximately 80% passing 50 mm and 0.5 inch refers to a sample 100% passing 16 mm or approximately 80% passing 12.5 mm.

All column leach test work reported no percolation problems; therefore, the use of cement agglomeration was not required. All of the column leach tests at the 16 mm sizes (0.5 inch) were performed at a temperature of 4 degrees Centigrade to simulate cold climate leaching. The 175mm (6 inch) and 62.5mm (2 inch) crush columns were too large to be contained in the refrigerator and were leached at ambient lab temperature. Previous work has shown only a minor (-1%) gold recovery difference between ambient and cold climate leaching.

Table 1 Column Leach Test Results - Bulk Surface Oxide Samples

Column Sample Description
and Location
Ambient
Temp
0 C*
Crush Size, inches
Calculated Head Grade
g/t Au
Extracted
Grade

g/t Au
Gold Recovery
%
Days of Leach
Consumption NaCN
kg/t
Addition Hydrated Lime
kg/t
Latte - 583150mE Trench
22.0
6
1.241
1.143
92%
68
0.40
0.99
Latte - 583150mE Trench
22.0
2
1.364
1.253
92%
46
0.50
1.01
Latte - 583150mE Trench
4.0
0.5
1.196
1.110
93%
46
0.54
1.00
 
 
 
 
 
 
 
 
 
Latte - 583350mE Trench
22.0
6
1.144
0.971
85%
68
0.41
0.99
Latte - 583350mE Trench
22.0
2
0.890
0.829
93%
46
0.55
1.01
Latte - 583350mE Trench
4.0
0.5
0.970
0.929
96%
46
0.55
0.98
 
 
 
 
 
 
 
 
 
Latte Mine Block**
4.0
0.5
9.541
9.069
95%
67
0.58
0.99
Supremo Mine Block**
4.0
0.5
5.551
5.457
98%
67
0.68
0.99
 
 
 
 
 
 
 
 
 
Supremo T2-T4 Composite
22.0
6
2.098
1.935
92%
67
0.53
1.49
Supremo T2-T4 Composite
22.0
2
2.053
1.914
93%
67
0.96
1.51
Supremo T2-T4 Composite
4.0
0.5
1.902
1.844
97%
67
0.59
1.49
 
 
 
 
 
 
 
 
 
Supremo T3 Composite
22.0
6
2.855
2.353
82%***
67
0.46
1.51
Supremo T3 Composite
22.0
2
2.280
2.120
93%
67
0.72
1.59
Supremo T3 Composite
4.0
0.5
2.256
2.153
95%
67
0.29
1.51

* The 2 inch and 6 inch crush columns were too large to be contained in the refrigerator and were leached at ambient lab temperature (220 C).
** The Latte and Supremo mine block samples were bulk samples taken at a continuous section of selected higher grade trench locations without any dilution intervals. Latte Mine Block was taken from the 583150mE Trench and Supremo Mine Block was taken from the 6974000mN Trench (T4)

*** The assay screen analysis of the tailings from this test indicated that 53 % of the gold lost to the tailings was contained in plus 100mm (4 inch) size fractions due to an assay of those fractions that was abnormally high. The plus 4 inch tailings assayed 1.48 g/t Au while the plus 4 inch head assay for the same sample was only 0.21 g/t Au. Due to the coarse particle size assaying accuracy is compromised.

Table 2 Column Leach Test Results - Drill Core Composites Oxide Samples

Column Sample Description and Location
Ambient Temp
0 C
Crush Size,
inches
Calculated Head Grade
g/t Au
Extracted Grade
g/t Au
Gold Recovery
%
Days of Leach
Consumption NaCN
kg/t
Addition Hydrated Lime
kg/t
Latte Oxide West
22.0
2
1.172
1.113
95%
45
0.48
1.52
Latte Oxide West
4.0
0.5
1.222
1.064
95%
45
0.17
1.53
 
 
 
 
 
 
 
 
 
Latte Oxide East
22.0
2
1.034
0.961
93%
81
0.87
1.53
Latte Oxide East
4.0
0.5
0.962
0.906
94%
81
0.30
1.52

 







Supremo Oxide West
22.0
2
1.306
1.171
90%
67
0.49
1.51
Supremo Oxide West
4.0
0.5
1.276
1.215
95%
67
0.84
1.50
 
 
 
 
 
 
 
 
 
Supremo Oxide East
22.0
2
1.668
1.590
95%
67
0.74
1.53
Supremo Oxide East
4.0
0.5
1.782
1.707
96%
67
0.32
1.49

 







Kona Oxide
22.0
2
1.415
1.245
88%
81
0.82
1.56
Kona Oxide
4.0
0.5
1.360
1.242
91%
81
0.37
2.06

 







Double Double Oxide
22.0
2
4.330
4.099
95%
81
0.87
1.56
Double Double Oxide
4.0
0.5
2.988
2.849
95%
81
0.32
2.02

Leach Kinetics of Latte and Supremo Samples
As experienced in earlier test work, the leaching kinetics of all samples was very rapid. Although the finer crush sizes do illustrate somewhat faster leaching, even the 6 inch crush samples leach extremely quickly. For illustration purposes, please view the supporting images associated with this metallurgical test work program by clicking the following link: http://kaminak.com/_resources/images/NR_MetSamplesOxide.pdf

Comparative Bottle Roll Test Work
Results from bottle roll test work undertaken on splits of the same composites utilized for column leaching are detailed below in Table 3. By using a fine grind, recoveries were not substantially increased over the column leach tests, indicating that heap leaching will most probably be economically more attractive than agitation leaching (given the lower capital and operating costs typically associated with heap leaching).

Table 3 Results of Bottle Roll Leach Tests


Description
Calculated Head Grade
g/t Au
Extracted Grade
g/t Au
Avg. Tails
g/t Au
Gold Recovery
%
Consumption NaCN,
kg/t
Addition Ca(OH)2,
kg/t
Latte - 583150mE Trench
1.063
0.930
0.133
87%
0.02
2.25
Latte - 583150mE Trench
1.078
1.018
0.060
94%
0.18
3.00
Latte - 583350mE Trench
0.919
0.856
0.063
93%
<0.01
2.25
Latte - 583350mE Trench
0.868
0.830
0.038
96%
0.08
3.00
Latte Mine Block
8.884
8.357
0.527
94%
0.08
3.50
Latte Oxide West
1.125
1.067
0.058
95%
0.08
2.50
Latte Oxide East
0.980
0.927
0.053
95%
0.06
2.50
 
 
 
 
 
 
 
Supremo Mine Block
5.020
4.912
0.108
98%
0.03
2.75
Supremo T2-T4 Composite
1.664
1.620
0.045
97%
<0.01
3.00
Supremo T3 Composite
2.399
2.322
0.077
97%
0.13
2.00
Supremo Oxide West
1.242
1.189
0.053
96%
0.02
2.00
Supremo Oxide East
1.777
1.717
0.06
97%
0.10
1.75
 
 
 
 
 
 
 
Kona Oxide
1.234
1.113
0.121
90%
0.31
2.50







Double Double Oxide
2.635
2.527
0.108
96%
0.15
2.50

Core Sample Selection for the 2014 - 2015 Metallurgical Test Program
All of the samples used for the core sample portion of column leach tests were composited from drill core consisting of a wide distribution of different drill holes and individual intervals to give a representative sample of each deposit area. Details of the metallurgical test work composite selection are provided in Table 4.

Table 4 Metallurgical Core Composite Selection

Sample Description
No. of Core Drill Holes
No. of Individual Drill Intervals
Latte Oxide West
5
67
Latte Oxide East
8
56
 
 
 
Supremo Oxide West
13
73
Supremo Oxide East
12
97
 
 
 
Kona Oxide
11
52
Double Double Oxide
7
67

QA / QC
Kaminak's disclosure of metallurgical data in this press release has been reviewed and approved by Fred Lightner, P.E., Director or Mine Development to Kaminak Gold Corporation, who serves as a Qualified Person under the definition of National Instrument 43-101. Disclosure of additional technical or scientific information in this press release has been reviewed and approved by Tim Smith, P.Geo., Vice President Exploration of Kaminak Gold Corporation, who serves as a Qualified Person under the definition of National Instrument 43-101.

On behalf of the Board of Directors of Kaminak

"Eira Thomas"
Eira Thomas President and CEO
Kaminak Gold Corporation

For further information about Kaminak Gold Corporation or this news release, please visit our website at www.kaminak.com or contact Tony Reda, Vice President of Corporate Development, at toll free 1.844.646.4520, directly at 604.646.4534 or by email at info@kaminak.com.

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

Caution Concerning Forward-Looking Statements

Certain disclosures in this release, including management's assessment of the future potential of the Coffee Project, costs and timings for completion of the Coffee Project feasibliity study and future exploration programs, constitute forward-looking statements that are subject to numerous risks, uncertainties and other factors relating to Kaminak's operations as a mineral exploration company that may cause future results to differ materially from those expressed or implied in such forward-looking statements, including risks as to the completion of the plans and projects. Readers are cautioned not to place undue reliance on forward-looking statements. Except as required by law, Kaminak expressly disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future event or otherwise.

The Company has not made a production decision, and the Company’s strategic plan to develop a stand-alone heap leach operation is subject to the results of its Feasibility Study. Further, if and when the Company makes any production decision, it will disclose the basis of such decision in accordance with the requirements of National Instrument 43-101 Standards of Disclosure for Mineral Projects (“NI 43-101”).





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