Mount Pearl, NL, Canada: Cornerstone Capital Resources Inc. ("Cornerstone") (TSXV-CGP) (F-GWN) (B-GWN) (OTC-CTNXF) today announced the sampling results of eight additional trenches and provided an update on the ongoing exploration program being carried out at the La Fortuna copper-silver project located in the Valparaíso Region of central Chile, approximately 100 km north of Santiago. Results from initial trenching and a general description of the exploration program were released on August 30, 2011, and included 1.34% copper and 58.0 g/t silver over 19.5 metres in trench TH1. A map showing the location of the La Fortuna project, as well as geology and updated exploration results can be viewed at www.cornerstoneresources.com.

Highlights

• Trench TH8: 117.9 m grading 0.19% Cu and 9.4 g/t Ag, including 52.4 m grading 0.33% Cu and 16.9 g/t Ag
• Trench TH12: 28.1 m grading 0.16% Cu and 1.9 g/t Ag
• Trench TH14A: 7.7 m grading 0.36% Cu and 11.6 g/t Ag
• Trench TH14B: 25.5 m grading 0.19% Cu and 6.2 g/t Ag

"Results from trenches TH8 to TH14B confirm that the potential for copper and silver mineralization is widespread over the La Fortuna property. Results from trench TH8 are particularly interesting as they confirm the potential for breccias, a porous unit, to host disseminated copper and silver mineralization over significant widths", commented Brooke Macdonald, Cornerstone's President and CEO. "Our geologists believe that this breccia may be located on the same stratigraphic horizon as the breccias hosting copper and silver mineralization at the neighbouring Cerro Negro mine. This hypothesis will have to be tested but La Fortuna continues to deliver very encouraging results, and we expect to have several promising drill targets defined in the coming weeks".

Exploration program
The La Fortuna property covers an area of approximately 2,900 hectares, measuring 10 km north-south by 3 km east-west. The project is favourably located in an established mining district at relatively low elevations (1200 to 1800 m above sea level), and is easily accessed by existing roads. The property is partly contiguous with the Cerro Negro copper-silver mine, a manto-type deposit immediately to the west which combines open pit and underground operations and produces copper cathodes via heap leach SX-EW and copper-silver concentrates via flotation. The El Bronce epithermal gold-silver district is located 30 km to the north. The region is sparsely populated, and has a hot and dry climate which is well-suited for leaching operations. Many surface mineral occurrences have been worked by small scale miners in the past but no drilling has ever been carried out at La Fortuna.

Significant copper and silver assay results were obtained in 2011 in the northern two-thirds of the property, defining seven prospective mineralized zones over a large area of approximately 18 km². Higher-grade mineralization is concentrated in, but not restricted to, veins that are typically 1 to 2 m wide but occasionally up to 4 m, emplaced within wider (up to 50 m) fault zones, often intruded by andesitic porphyry dykes. A structural analysis defined two main structural trends, with the most prominent orientation at N45 to N70 degrees and a second set, striking N320 degrees. Mineralization is also present as disseminations in fractures and shear zones within halos to the structures and within breccias over significant widths (up to 117.9. m in trench TH8, see assay results below). Information collected thus far suggests that mineralizing fluids migrated along steeply dipping structures and metals were deposited within the structure and wall rocks and within geochemically receptive, sub-horizontal, geological horizons and higher porosity, brecciated rocks. The presence of intrusive rocks (stocks, dykes, etc.) appears to be an important controlling factor for the deposition of mineralization.

The surface exploration program initiated in April 2011 is now well advanced. Prospecting work was carried out over the entire property and more detailed ground exploration surveys focused on the northern two-thirds of the property. This latter work included geological and structural mapping, a 217 line kilometre ground magnetic survey and a 39.8 line kilometre, deep penetrating (400 meters), Induced Polarization (IP) survey. A total of 168 rock samples were collected during the prospection and geological mapping program. Nineteen (19) trenches totaling 710.1 metres were dug and channel sampled (348 samples). Data from the IP survey has just been received and is currently being assessed. All the data generated on the project is currently being integrated into a 3D model to define drill targets. Additional trenches are required to test mineralized structures and IP and magnetic anomalies.

Trenching
Results from trenches TH1 to TH7 were released on August 30, 2011 with TH1 returning 19.5 m at 1.34% Cu and 58.0 g/t Ag. Table 1 below provides assay results for trenches TH8 thru TH14B; results for trenches TH15A, TH15B and TH15C are pending.

0 Table 1. La Fortuna Trenching Results.

Trench	Zone	Length (m)	# Samples	Interval (m)*	Cu (%)	Ag (g/t)
TH8	Loma Verde Sur	117.9	58	117.9	0.19	9.4
			including	8	0.08	2.2
			and	52.4	0.33	16.9
			and	17.2	0.09	6.0
			and	20.3	0.09	4.6
TH9	Guayacan	41.5	20	4.0	0.34
				5.5	0.12
TH10	Guayacan	34.8	17	No Significant Values
TH11	Guayacan	10.5	5	2.2	0.51	4.8
TH12	Qda. Honda	28.1	14	28.1	0.16	1.9
TH13	Qda. Honda	53.8	27	2	0.17	1.3
TH14A	Loma Verde	7.7	4	7.7	0.36	11.6
TH14B	Loma Verde	26.3	13	26.3	0.18	6.0
TH15A	Qda. Honda	52.0	25	Assay Results Pending
TH15B	Qda. Honda	5.5	2	Assay Results Pending
TH15C	Qda. Honda	4.0	2	Assay Results Pending
		382.1	187

* The reported copper and silver intervals are apparent thicknesses due to the early nature of the exploration program.

Discussion
The most significant assay results have been obtained from trenches TH8, TH12, TH14A and TH14B. Results for TH8 are particularly significant in the sense that the extensive breccia unit mapped on that part of the property appears to be geologically correlative with the brecciated geological horizon ("Diablo" breccia) hosting the main copper-silver mineralization at the neighbouring Cerro Negro mine. Copper-silver mineralization in TH12 is associated with a contact between the sub-volcanic andesitic rock and the volcano-sedimentary sequence. These results confirm our preliminary interpretation that the faulted intrusive-host rock contact zone is prospective and should be drill tested. Trenches TH14A and TH14B were dug to test a northeast oriented structure located at approximately the same stratigraphic level as trench TH8. Results from these two trenches confirm the prospectivity of the breccia horizon. Mineralization in the Guayacan area (trenches TH9, TH10 and TH11) appears to be restricted to the structures with only minor disseminated mineralization in the wall rocks.

Sampling and assaying
All samples are delivered by Cornerstone employees for preparation at Acme Analytical Laboratories (ACME) facility in Santiago, Chile. Rock samples are prepared crushing 1 kg to 80% passing 2 mm (10 mesh), splitting 250 g and pulverizing to 85% passing 0.075 mm (200 mesh) (ACME code R200-250). Gold is assayed in Chile, using a 30 g split, Fire Assay (FA) and AA or ICP-ES finish (ACME code G601). A 100g-plup is shipped to ACME in Vancouver, Canada where samples are assayed for a multi-element suite (ACME code 1DX2, 15g split, Aqua Regia digestion, ICP-ES finish). All samples with results > 100 g/t Ag, >10,000 ppm Cu, Pb or Zn are systematically and quantitatively re-assayed (ACME code 7AR, Aqua Regia Digestion, ICP-ES finish). All samples with results > 5,000 ppm Cu total are systematically re-assayed to determine leachable copper (ACME code G9, Citric acid leach, Cu, 1 g/100 mL, AAS finish).

Quality assurance / Quality control (QA/QC)
ACME is an ISO 9001:2008 qualified assayer that performs and makes available internal assaying controls. Certified blanks and standards are systematically used as part of Cornerstone's QA/QC program. One of them was inserted every 20 samples at La Fortuna.

Qualified Person
Yvan Crepeau, M.Ba., P.Geo., General Manager of Minera Cornerstone Chile Limitada (MCCL) and a qualified person in accordance with National Instrument 43-101, is responsible for supervising the exploration program at the La Fortuna project and has reviewed and approved the information contained in this news release.

La Fortuna option agreement
Cornerstone, through its wholly-owned subsidiary, MCCL, has entered into an agreement with a Chilean individual to acquire the La Fortuna property. The agreement gives Cornerstone the right to acquire an undivided 100% interest in the La Fortuna property by incurring exploration expenditures of C$3.0 million and making cash payments totalling C$600,000 over a 4-year period. Requirements to maintain the agreement through the first year include a cash payment of C$100,000 and exploration expenditures of C$500,000. The acquisition is subject to a 1.5% Net Smelter Royalty ("NSR"), and to advance payments of the NSR on each anniversary following the date the option is exercised. Cornerstone has a right of first refusal to purchase the NSR if the holder decides to sell it.

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