Trenching of the Melisa target at Montezuma exposes mineralised porphyry and significant copper mineralisation

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TORONTO, May 28, 2013 /CNW/ - Polar Star Mining Corporation (TSX: PSR) ("Polar Star" or the "Company") is pleased to announce the results of its recent trenching program which has shown the existence of copper mineralisation throughout the target area plus the identification of two mineralised porphyry structures.


Highlights

- 3,900 metres of trenching completed at the Melisa target within Polar Star's 100% owned Montezuma exploration area

- Mineralised porphyry identified in two locations within the Collapse Zone at Melisa

- Significant mineralisation identified within the Fault Elbow zone at Melisa which showed 1.18% copper over 22 metres of trenching

- Other trench areas within the Mina Negra and Haroldo zones at Melisa returned significant results including an intersection of 14 metres at 0.93% copper and a separate vein recording 5.43% copper over 2 metres

Commencing in late 2012, Polar Star refocused its exploration program at Montezuma. The structural interpretation of fault relationships, detailed analysis of the previous drilling and the reprocessing of the ground and airborne geophysics directed the program. Five new areas for follow up exploration were identified. Melisa and Ignacia in the north and Patricia, Dyana and Karina in the south-central section of the property.

Field observations confirmed that all five areas have the potential to host copper porphyry deposits. After review Melisa was chosen as the first area for immediate follow up based on:

- Proximity to the Codelco Chuquicamata and Minstro Hales mines.
- The size and intensity of the area of stock work
- The significant concentration of artisanal copper oxide mining

The Melisa anomaly is a zone stock work, of collapsed structures and copper and tourmaline veining covering an area of approximately 4km x 4km in the northeast sector of the Montezuma property.

The ongoing Niton spectrometer survey has outlined areas of coincident copper, arsenic, bismuth and molybdenum values. A trenching program was designed to test the anomalies outlined by geological mapping, the Niton program, and the reinterpretation of the geophysics. 35 trenches were completed totalling 3,900 metres. Polar Star has to date received approximately 60% of the results back with the balance expected to be received in the coming weeks.

As shown in the map in Appendix 1, three areas were initially targeted in the western part of the stock work zone:

1. Mina Negra and Haroldo
2. Fault Elbow
3. Collapse Zone

Within the Mina Negra and Haroldo stock work areas, local artisanal miners have historically worked the extensive vein systems. The spectrometer and channel sample assays identified anomalous values for copper, arsenic, molybdenum and bismuth over an area of 1km x 2km, confirming that the stock work is mineralised across the whole zone. The values include a 14 metres section grading at 0.93% copper and a separate 2 metre section grading at 5.43%.

The Fault Elbow anomaly located 1 km south of Mina Negra is the result of the interaction between N-S and NE-SW faulting. Artisanal vein mining exploited not only copper but also lead and zinc from this area. Grab samples taken from these vein sections include high copper values of 4.05%, 4.87% and 6.25%. A sample taken from one of the lead / zinc veins grades 2.54% Pb, 1.76% Zn and 49.9 ppm silver. Additionally, seven trenches were cut in the central section of the Fault Elbow area covering 22 metres. The average grade over this 22 metres of trenching was 1.18% copper.

The focus of the exploration program has been in the Collapse Zone area. This area is characterised by circular collapse structures and strong hematite and tourmaline stock working. The ongoing Niton spectrometer program, identified a 250m x 500m area in the west where coincident high values for copper, arsenic and molybdenum occur. The first two trenches in the area exposed mineralised porphyry structures. The main exposure in Trench No1 is 6 metres wide and grades at 0.18% copper. The presence of a chilled margin shows that this is the top of the system, where leaching of the grade can occur. Ninety metres to the south, in Trench No 2, is a second porphyry exposure one metre in diameter. Sampling over the 10 metre long trench which includes this 1 metre porphyry section returned an average grade of 0.89% copper.


Colin Bird, President and CEO stated:

"Our goal at Montezuma is to outline areas where the geological and geophysical markers provide sufficient confidence to define future exploration work and drill targets.

This exposure of mineralised porphyry, representing only a small section of the area under investigation, has significantly increased the possibility for the discovery of a world-class copper porphyry system. Although we are in the early stage of our program, we are delighted with the results, not only with the discovery of the porphyry but also the existence of extensive copper mineralisation throughout the target area. Our next step is to carry out ground geophysics and thereafter drill the most prospective targets. Drilling is currently targeted for third quarter 2013."


Sampling and Laboratory

Trench samples were sent to ALS Chemex, a fully accredited and certified laboratory service. Samples were prepared at the ALS Chemex facility in Chile, and assayed at ALS Chemex in Lima, Peru.


Qualified Person

Colin Bird, is a qualified person under NI 43-101, and has reviewed and approved the technical information contained in this press release.


About Polar Star Mining Corporation

Polar Star Mining Corporation ("PSR") is a TSX listed exploration and development company with a focus on building shareholder value in Chile. The Company's strategy is to use the cash flow from its' Chepica mine (primarily gold) to fund, in part, the exploration program at its flagship Montezuma property and to advance our large portfolio of other world class projects in Chile through joint ventures. www.polarstarmining.com


'signed'
Colin Bird, President, Chief Executive Officer and Director



Image with caption: "Appendix 1: Montezuma - Melisa Stock work Zone (CNW Group/Polar Star Mining Corporation)". Image available at:
http://photos.newswire.ca/images/download/20130528_C2783_PHOTO_EN_27177.jpg



For further information:

Martin Gallon, Chief Operating Officer
Polar Star Mining Corporation
Email: info@polarstarmining.com
Telephone: (540) 256-1444