Sep 12 2014
Cornerstone Capital Resources Inc. ("Cornerstone" or "the Company") announces the following project update for the Company's Cascabel copper-gold porphyry joint venture exploration project in northern Ecuador.
HIGHLIGHTS:
- As of September 9th, Hole 8 had reached a depth of 606.5m. Visible copper sulphide mineralization commences from 378.2m.
- Preliminary resistivity/conductivity modeling from IP survey supports geological model and presence of porphyry targets.
- Preliminary metallurgical results from rougher flotation testwork show 91-98% recovery of copper and gold.
- Second drill rig ready to be mobilized to Cascabel upon completion of IP modeling.
All reported intervals referred to in this news release are core lengths. At present the true thicknesses are uncertain due to the early stage of drilling.
References to figures and photographs related to the version of this release on the Company's website (www.cornerstoneresources.com) or visible in PDF format by clicking the link below:
http://www.cornerstoneresources.com/i/pdf/NR14-22Figures.pdf.
Further Information
Hole CSD-14-008
Hole CSD-14-008 ("Hole 8") at the Alpala copper-gold porphyry target, the main prospect within the Cascabel concession located in northwest Ecuador (Figure 1, location) reached a depth of 606.5m on September 9th, and drilling continues. The drillhole has encountered visible copper sulphide mineralization from a depth of 378.2m with increasing mineral alteration intensity, indicating increasing proximity to the modeled intrusive copper-gold porphyry source. Hole 8 commenced on August 15th and is testing a large magnetic feature modeled by the Magnetic Vector Inversion technique (MVI) (Figure 3). The magnetic feature is present over a northwest extent of 1,100m and is at least 500m wide. This feature extends over a vertical dimension of almost 1000m, from a depth of approximately 800m to 1800m, and is supported by an intersection in Hole 5, completed on February 21, 2014. Hole 5 intersected 1,306m grading 0.62% Cu and 0.54 g/t Au from a depth of 24m to 1330 metres. This intersection included high-grade intervals of 552m grading 1.03% Cu and 1.05 g/t Au from 778m and 258m grading 1.27% Cu and 1.4 g/t Au from 1052m to 1310 metres. The Alpala system to date is considered to be a high grade copper-gold porphyry system as evidenced by the interval from 1096m to 1146m in Hole 5 which yielded 1.80% Cu and 2.26 g/t Au. For more information on Hole 5, see Cornerstone news release 14-07 of March 3, 2014.
IP Geophysical Survey
Exploraciones Novomining S.A. ("ENSA"), the Ecuadorean company owned 85% by SolGold Plc and 15% by Cornerstone, commissioned a 14km2 Induced Polarization and Magneto Telluric Resistivity survey over the Alpala prospect and environs to more accurately model alteration, stockwork quartz veining and sulphide content to assist with drillhole targeting. The survey set-up commenced on July 18th and collection of data was completed on August 19th. The three dimensional survey, conducted by Quantec Geophysics (Toronto, Canada) comprised the collection of information from approximately 150,000 data points in a three dimensional grid to a depth of approximately 2000m for resistivity/conductivity data and 800m for chargeability data. The survey was designed to interrogate both the upper clay, pyrite, and silica altered zones above the porphyry system and the porphyry system itself.
At the date of this report, processed data had been received from Quantec and ENSA's geophysical consultant has provided preliminary interpretation of the galvanic resistivity survey above 800m. The interpretation (Figure 2) shows 8 stronger conductive zones that lie within 3 parallel north-northwest orientated conductive zones to a depth of at least 800 metres, within a northwest-southeast oriented 3km by 2 km conductivity halo. The data shows that the strong conductivity anomalies "C1" and "C2" (Figures 2, 3 and 4) lie above the MVI magnetic spire that is the current principal target. The "C1" conductivity anomaly (Figure 2) lies in the area of current drilling at Central Alpala and overlies the principal magnetic anomaly at Central Alpala, reinforcing that the magnetic anomaly is the locus of core potassic alteration. On section (Figure 3), this magnetic anomaly is about a kilometre wide at a depth 1200m below surface.
ENSA has identified further preliminary conductivity targets to the northwest and southeast of Central Alpala which are now supported by both magnetic and resistivity models.
Further targets are expected to be defined on the southwest and the northeast conductive zones. In addition, the Company expects to define additional targets in the porphyry system by interpreting chargeability data that is still to be finally processed, and magneto telluric resistivity data to a depth of up to 2 kilometres, also yet to be finally processed. Final processing of all IP and magneto-telluric data is expected within the next 2-4 weeks.
Metallurgical Testwork
Preliminary metallurgical results have been received on 3 composite samples from Hole 5 indicating rougher circuit flotation recoveries at grind sizes between 50 and 150 micron of between 91-98% copper and gold.
ENSA continues to investigate optimization of metallurgical recoveries and further testwork is required on a variety of head grade samples to refine these results.
Second Drill Rig
ENSA has engaged a second drill rig which is ready to be mobilized to Alpala. The rig is expected to be operational by mid October and will be deployed to test targets refined as a result of final IP and resistivity survey interpretations.
About Cascabel
SolGold Plc owns 85% of the equity of Exploraciones Novomining S.A. ("ENSA"), an Ecuadorean registered 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 with Cornerstone Ecuador S.A. providing some exploration and administrative services. Cornerstone's 15% interest is financed through completion of a National Instrument 43-101 compliant 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. (Mineralization identified at the Cu Junin copper project is not necessarily indicative of the mineralization on the Cascabel Property).
Qualified Person:
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 Cornerstone's core logging facility and half of the core is delivered by Cornerstone employees for preparation at Acme Analytical Laboratories (ACME) affiliate laboratory in Cuenca. Core 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). Prepared samples are then shipped to ACME in Vancouver, Canada where samples are assayed for a multi-element suite (ACME code 1E, 0.25g split, 4-acid digestion, ICP-ES finish). Over limit results for Ag (> 100 g/t), Cu, Pb and Zn (each one > 1%) are systematically re-assayed (ACME code 7 TD1 or 7 TD2, 4-acid digestion, ICP-ES finish). Gold is assayed using a 30 g split, Fire Assay (FA) and AA or ICP-ES finish (ACME code G601).
Quality assurance / Quality control (QA/QC)
The ACME affiliate preparation facility in Cuenca was audited by Cornerstone prior to the start of the drilling program and ACME is an ISO 9001:2008 qualified assayer that performs and makes available internal assaying controls. Duplicates, certified blanks and standards are systematically used (1 control sample every 15 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.