Cerro Delta
The deposits of the Maricunga Belt are often very large but low grade porphyry gold-copper type deposits with variably oxidized sulfide stockwork or veinlets with or without associated copper (Maricunga, Volcan, Caspiche, Cerro Casale) or high sulfidation type epithermal quartz veins and stockworks with better grades and without copper (La Coipa, Lobo-Marte). It is common to have both deposit types in a single large deposit area such as is the case with the Cerro Delta project. In addition, most deposits in the Maricunga Belt exhibit a zoned alteration pattern with an area of potassic alteration flanked by argillic and advanced argillic alteration with some amount of silicification, which is also common to Cerro Delta. Also common to deposits of the Maricunga Belt are large scale faults and lineaments of a general north-south trend and which tend to localize the emplacement of mineralized intrusions. At Cerro Delta these regional structures are mostly N-S, NNW and E-W with several intersecting zones which appear related to alteration and mineralization.
Gold mineralization at Cerro Delta is hosted in both a Miocene porphyry (Cerro Porfiro) and a peripheral high sulphidation epithermal system (Cerro Delta). The mineralization in the porphyry is in a stockwork system of quartz and sulphide veinlets mainly emplaced in the potassic alteration zone with gold contents in rock samples at surface grading up to 0.8 g/t. In the epithermal system the gold is in siliceous breccias with gold contents up to 4.0 g/t. There are large +100 ppb gold-in-soil anomalies that cover both the porphyry and the epithermal mineralization which are also coincident with IP geophysical anomalies. The entire auriferous zone which overlays the porphyry and the epithermal system is approximately 1.5 km by 2km in size.
A geophysical program was performed on Cerro Delta in 2008 which outlined several large IP anomalies that are associated with both the Cerro Porfiro (high chargeability) and Cerro Delta (high resistivity) areas, another characteristic in common with the known deposits along the Maricunga belt. At Cerro Delta these IP chargeability anomalies extend to 1,000 m by 600 m in area. Coincident with the IP anomalies are two areas of gold-in-soil anomalies with anomalous values from 25 to over 100 ppb gold that form several contiguous zones measuring up to 200 m by 800 m in area. Similar gold in soil anomalies are noted over the Refugio, Caspiche and Cerro Casale deposits. For example, the gold in soil and rock chip anomalous gold zone originally mapped by Anglo American at Capiche measured 650 by 300 meters.
The Cerro Delta project is drill ready and the company intends to begin drilling in the first quarter of 2012.
The Maricunga Gold Belt:
The Maricunga Gold Belt extends approximately 200 kilometers north-south and 40 kilometers east-west, straddling the border between Chile and Argentina. Some of the more significant gold-copper deposits located within the Maricunga Gold Belt are, from north to south:
| Name | Company | Gold Ozs./Grade | Copper Lbs/Grade |
| La Coipa | Kinross | 2.6 mm/1.17 g/t | |
| Lobo-Marte | Kinross | 5.9 mm/1.19 g/t | |
| Volcan | Andina | 9.8 mm/0.69 g/t | |
| Maricunga/Refugio | Kinross | 9.3 mm/0.66 g/t | |
| Caspiche | Exeter | 26.4 mm/0.55 g/t | 6.7 B lbs/0.22 % |
| Cerro Casale | Barrick | 28.8 mm/0.56 g/t | 7.8 B lbs/0.21 % |
Cerro Delta Project Location
Ideal location --sparsely populated but highway access, at a lower altitude, and easier working terrain than established operations.
The Cerro Delta project is located in the far northwest of La Rioja Province in Argentina, only a few kilometers from the border with Chile. It is located just 20 kilometers east of the Cerro Casale deposit and 29 kilometers southeast of the Caspiche deposit, at an elevation of about 4,500 meters above sea level in the Cordillera de los Andes. The area is quite remote from any established towns, but is close to an improved highway crossing the border into Chile where the closest town is Copiapo. While quite high in elevation, the area consists of barren rolling hills. By contrast the Pascua Lama operation is located near glaciers at about 5,200 meters in elevation.
Mining Friendly Province
Argentina is a federal country divided into Provinces which manage non-renewable resources according to the National Mining Code and Provincial laws. Some provinces such as Chubut are opposed to mining. The mining friendly Provinces in Argentina, include La Rioja where Pan American is active and which is located between two major mining Provinces. The first province, the Catamarca Province, contains the Xstrata operated Bajo de la Alumbrera mine and the Agua Rica project which Gold Corp and Xstrata just optioned from Yamana Gold. The second province is the San Juan Province where Barrick Gold's Veladero produced 611,000 ounces in 2010 and the Pascua Lama is projected to produce an average of 750,000 -- 800,000 ounces of gold annually for the first five years of production beginning 2013. The San Juan Province also contains Yamana's Gualcamayo operation which it acquired via the purchase of Viceroy Exploration in 2010.
Cerro Delta Geology & Area's Mining Type
The Cerro Delta project is a porphyry type deposit (Cerro Porfiro) as well as an epithermal system (Cerro Delta). Most of the Maricunga deposits have a typical zoned alteration pattern with a potassic alteration area flanked by argillic and advanced argillic alteration with some amount of silicification. This is also the case for the Cerro Delta project, as are large scale faults and lineaments of general north-south trend, which tend to localize the emplacement of mineralized intrusions common to deposits of the Maricunga Belt.
At Cerro Delta the regional structures are mostly N-S, NNW and E-W with several intersecting zones which seem related to alteration and mineralization. Current and proposed mining operations in the Maricunga are comprised of mostly open pit mining with crushing of oxide ore followed by heap leaching, crushing and grinding followed by tank cyanidation and milling and flotation to make a gold-copper sulfide concentrate for sale to a smelter.
Exploration Model and Resource Potential
The resource potential of the Cerro Delta project is based on its proximity and geological similarity to other large deposits in the Maricunga Gold Belt. While the first round of drilling is not planned until Q4 2011, based on the exploration work and results to date, the similarity to comparable known deposits, and the overall size of the known anomalous areas, there is potential for a multi-million ounce deposit.
The first exploration work done on the property was performed by the company Eldorado S.A. (1996-1997) who defined a large gold in soil anomaly and a strong IP (Induced Polarization) anomaly in the area of both Cerro Porfiro and Cerro Delta. Eldorado also put in several large trenches in the area with gold values in rock up to 0.8 g/t associated with stockwork sulfide veinlets at Cerro Porfiro and up to 4.0 g/t in silicified breccias at Cerro Delta. They quit the country when commodity prices began to erode in about 1998. The exploration company Golden Peaks (March-April 2008) confirmed the encouraging IP results of Eldorado. The IP anomalies at Cerro Delta are associated with both the Cerro Porfiro and Cerro Delta localities. The combination of high chargeability and a high resistivity are characteristic of the known deposits along the Maricunga belt. They correlate with large gold in soil anomalies that have been mapped on the project. This adds to the potential for a discovery as similar gold in soil anomalies are noted over the Refugio, Caspiche and Cerro Casale deposits.
Maps & Photos
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