Cornerstone Capital Resources Inc. ("Cornerstone" or "the Company") announces the following project update for the Cascabel copper-gold porphyry joint venture exploration project in northern Ecuador, in which the Company has a 15% interest financed through to completion of a feasibility study. SolGold Plc is funding 100% of the exploration at Cascabel and is the operator of the project.
Hole 16 - Alpala Central Deposit
- Hole 16 at a depth of 1,178m.
- Mineralization increasing in intensity.
- Over 650 metres of mineralization encountered thus far.
- Hole 16 Assay Received from 516m to 764m:
- 216m @ 0.96 % Copper and 1.27 g/t Gold from 548m (1.73% CuEq, open at depth), including:
- 60m @ 2.01 % Copper and 3.41g/t Gold from 704m (4.06% CuEq, open at depth).
- Intense multidirectional quartz-magnetite-copper sulphide veining in drill core.
- Increasing intensity of bornite (a copper sulphide mineral containing 63% copper) down hole and to the south east.
- Trivino Prospect drilling planned based on confirmation of copper-gold anomalism up to 0.43% Cu and 0.43g/t Au at surface.
All reported intervals referred to in this news release are core lengths. At present the true thicknesses of Hole 16 intersections are uncertain due to the early stage of drilling.
Figures, photographs and tables referred to in this news release can be seen in PDF format by accessing the version of this release on the Company's website (www.cornerstoneresources.com) or by clicking on the link below:
Central Alpala Deposit
On Tuesday 1 March 2016 at 12 noon Ecuador time, Hole 16 (CSD-16-016) was drilling ahead at a depth of 1,178m. The drill hole continues to encounter intense porphyry style copper-gold mineralization at the Alpala deposit in Northern Ecuador. The Cascabel Project is located within the northern portion of the Andean copper belt, renowned as the host of 48% of the World's copper production, and numerous Tier 1 global resource assets (refer Figure 1 Regional Setting).
Cascabel boasts numerous large porphyry copper-gold targets within a cluster of prospective porphyries in a relatively unexplored section of the Andean copper belt. SolGold enjoys the support of and the Ecuadorean Government in developing the nation's exploration and mining industry. Cascabel presents numerous logistic advantages which augment its likely large scale and high copper gold grades. It is located on a sealed multi-lane national highway at a low elevation with abundant water, labour, hydroelectric power, and a short 80km distance to a Pacific deep water port site and 150 kms to an established deep water port at Esmeraldas (refer Figure 2 Location Map).
Hole 16 at Alpala has a planned depth of 1,800m and is currently drilling ahead at the rate of approximately 30 metres per day, without difficulties. The hole is projected to intersect the upper surface of the typically high grade Quartz Diorite intrusive phase at a depth of 1,270m. The intersections achieved in Hole 16, increases the known strike extent of copper and gold mineralization along the greater Alpala trend to over 650m. The Alpala Central deposit, which outcrops in Alpala Creek, is open virtually in all directions, and is to date defined over a strike length of over 450m, an average lateral width of 250m, and a vertical extent of 1,800m (refer Figure 3 Three Dimensional Model).
Hole 16 is being drilled at an declination of 85 degrees towards the south south west (198 degrees), and targets extensions 100m to the south east of Hole 12 which delivered a record result for the project of 1,312m at 0.67% copper and 0.63g/t gold (for 1.05% CuEq), including 576m at 1.03% copper and 1.19g/t gold (for 1.75% CuEq) in the high grade section.
First assay results for Hole 16 have been returned for the section from 514 metres to 764 metres a distance of 250 metres, returning:
216m @ 0.96 % Cu, 1.27 g/t Au from 548m (* 1.73% CuEq, open at depth), including:
60m @ 2.01 % Cu, 3.41 g/t Au from 704m (*4.06% CuEq, open at depth)
*Note : Cu-equivalent (CuEq) grade is calculated by following equation: Cu Eq. = Cu% + (Au g/t x 0.6). Cu-Equivalent values do not take into account the recoverability of gold.
The results confirm the strong extension of the Alpala Porphyry system to the south east of Hole 12.
Photographs of the recently encountered mineralization show intense porphyry style stockwork veining and mineralization (refer Figure 4 Core Photos).
The extension of Alpala Central to the south east is accompanied by increased intensity of bornite mineralization at surface and increasing intensity of veining with depth. Hole 16 has now encountered over 650m of strongly mineralized porphyry host rocks. Sub-horizontal vein sets and the prevalence of strong magnetite alteration (a magnetically susceptible iron-oxide mineral used as a temperature proxy to high temperature copper mineralization in porphyry systems) support the veracity of significant mineralization potential surrounding the Alpala Central system (refer Figure 5 Three Dimensional Magnetic Model).
At depth, the deposit remains open and is expected to continue for a further 500-800m vertically.The Alpala Structural Zone in which the Alpala Central deposit is hosted, has a vertical extent of over 2km and a length of 2.5kms and a width of up to 500 metres. Additional targets on the Alpala Structural Zone include Cristal, Alpala southeast, and Alpala northwest. The strong relationship between copper grade and magnetite content lends credibility to the very large size Magnetic 3D model as a very large copper gold porphyry target (refer Figure 5).
Sample assay results for surface rock saw channel sampling at Trivino have been received and indicate surface copper gold mineralization of up to 0.43% copper and 0.43g/t gold. The mineralization occurs within volcanic rocks within the upper argillic clay altered zone interpreted to lie above a significant copper porphyry system responsible for the mineralization. The prospect covers an area of 300 x 400 metres at surface, more extensive than the Alpala Creek discovery out crop. Trivino has been advanced to drill-ready status and a drilling platform has been identified. Subject to the results of Hole 16, rig availability and logistics, SolGold intends to drill this target in the next quarter, along with the promising outcropping Aguinaga Prospect located 1.2kms north east of Alpala Central (refer Figure 6).
SolGold Plc owns 85% of the equity of Exploraciones Novomining S.A. ("ENSA"), an Ecuadorean company that holds 100% of the Cascabel concession in northern Ecuador. Cornerstone owns the remaining 15% of ENSA, which also holds the rights to the La Encrucijada gold-silver project. SolGold is funding 100% of the exploration at Cascabel and is the operator of the project. Cornerstone's 15% interest is financed through completion of a feasibility study.
Cascabel is located in north-western Ecuador in an under-explored northern section of the richly endowed Andean Copper Belt, 60 km northeast of the undeveloped inferred resource of 982 million tons at 0.89% Cu Junin copper project (0.4% Cu cut-off grade; Micon International Co. Ltd. Technical Report for Ascendant Exploration SA, August 20, 2004, pages 28 & 29). Mineralization identified at the Junin copper project is not necessarily indicative of the mineralization on the Cascabel Property.
Yvan Crepeau, MBA, P.Geo., Cornerstone's Vice President, Exploration and a qualified person in accordance with National Instrument 43-101, is responsible for supervising the exploration program at the Cascabel project for Cornerstone and has reviewed and approved the information contained in this news release.
Logging, sampling and assaying
Holes referred to in this release were or are being drilled using HTW, NTW, NQ and BQ core sizes (respectively 7.1, 5.6, 4.8 and 3.7 cm diameter). Geotechnical measurements such as core recovery, fracturing, rock quality designations (RQD's), specific density and photographic logging are performed systematically prior to assaying. The core is logged, magnetic susceptibility measured and key alteration minerals identified using an on-site portable spectrometer. Core is then sawed in half at the ENSA core logging facility, and half of the core is delivered by ENSA employees for preparation at ALS Minerals Laboratories (ALS) sample preparation facility in Quito. Core samples are prepared crushing to 70% passing 2 mm (10 mesh), splitting 250 g and pulverizing to 85% passing 75 microns (200 mesh) (ALS code CRU-31, SPL21 and PUL-32). Prepared samples are then shipped to ALS in Lima, Peru where samples are assayed for a multi-element suite (ALS code ME-ICP61, 1g split, 4-acid digestion, ICP-AES finish). Over limit results for Ag (> 100 g/t) and Cu, (> 1%) are systematically re-assayed (ALS code Ag-AA62, 4-acid digestion, AAS finish). Gold is assayed using a 30 g split, Fire Assay (FA) and AA finish (ALS code Au-AA23).
Drill hole intercepts are calculated using a data aggregation method, defined by copper equivalent cut-off grades and reported with with up to 10m internal dilution, excluding bridging to a single sample. Copper equivalent grades are calculated using a gold conversion factor of 0.6, determined using copper price of US$3/pound and gold price of US$40/gram.
Quality assurance / Quality control (QA/QC)
The ALS Laboratory is a qualified assayer that performs and makes available internal assaying controls. Duplicates, certified blanks and standards are systematically used (1 control sample every 15-20 samples) as part of Cornerstone's QA/QC program. Rejects, a 100 g pulp for each core sample and the remaining half-core are stored for future use and controls.
SolGold has announced it is planning a resource statement at Alpala, the most advanced target at Cascabel, during 2016, in addition to drill testing the other key targets at Aguinaga, Trivino, Tandayama America and Chinambicito in the Cascabel concession. By the end of 2016 SolGold has reported it is planning further metallurgical testing, and completion of early stage mine and plant design and a scoping study for an economic development at Cascabel. SolGold is investigating both high tonnage / low grade open cut and high grade / low tonnage underground developments as a block caving operation.
Readers are cautioned that the potential quantity and grade of any resource at Cascabel is currently conceptual in nature, there has been insufficient exploration to define a mineral resource and it is uncertain if further exploration will result in the Alpala target being delineated as a mineral resource.