The Llancahue project is 100% owned by Coro and is located 38km south west of the City Of Talca in the VII Region of central Chile, at an elevation of less than 200m above sea level.
In November 2014, Minera Peñoles de Chile Ltda (“Peñoles”), a subsidiary of Mexican mining company, Industrias Peñoles SAB de CV entered in an option to acquire a 70% interest in the project. Coro announced the termination of this option agreement in October 2016.
Geology and Mineralization
The Llancahue property was staked in 2007 by Coro in recognition of its potential to host significant porphyry copper style mineralization. The Company had concluded that the Chilean Upper Cretaceous/Lower Tertiary porphyry belts may extend farther south than hitherto recognized, and accordingly initiated a reconnaissance exploration program following up known mineral occurrences and ASTER satellite derived alteration anomalies. Llancahue was the site of an old working for copper, and attractive copper sulphide mineralization hosted by potassically altered and brecciated diorite was present on its dump. The old workings were located on the edge of an extensive covered area, bordered to the north by propylitically altered diorites and andesites, containing disseminated magnetite.
In 2008, the Company entered into an exploration agreement with Freeport-McMoRan Exploration Corp (“Freeport”) whereby Freeport could earn an interest in Llancahue and other Coro owned exploration properties in the Talca Belt by committing to certain expenditures, including drilling. Freeport completed their first year expenditures and drilled 7 reverse circulation (RC) holes at Llancahue, but elected to withdraw from the agreement, after only the last hole in their program, LLA-07, intersected significant mineralization.
In 2009, a 6-hole reverse circulation drill program was completed, including an intercept of 100m at 1.37% copper. The drilling to date suggests that this mineralized intrusive and its brecciated contact zone is of restricted areal extent. However, the intensity of the alteration and the accompanying high grade copper molybdenum mineralization, together with the extensive propylitic halo, support the concept that a larger body of mineralized diorite or breccia complex may be present.
Mineralization at Llancahue, as currently understood, is hosted by an apical hydrothermal breccia developed around a sub vertical finger of strongly potassically altered diorite, and comprises disseminated and veinlet chalcopyrite, bornite and molybdenite. The drilling to date suggests that this mineralized intrusive, and its brecciated contact zone is of restricted areal extent. However, the intensity of the alteration and the accompanying high grade copper molybdenum mineralization, (which is anomalous in Bi), together with the extensive propylitic halo, support the concept that a larger body of mineralized diorite may be present under cover to the west of the area drilled. This is further supported by the presence of strongly potassically altered, chalcopyrite and bornite mineralized breccia float found in two other locations on the property, and by the increasing intensity of alteration around the northern and western margin of the covered area.
In December 2009, Zonge Ingeniería y Geofísica (Chile) S.A., completed a ground magnetic survey over the Llancahue property, extending an existing survey completed by Freeport.
Zonge concluded that copper and molybdenum mineralization observed in drillhole intersections generally correlates to zones of low magnetization (RTP lows or shallow zones of low 3D model magnetic susceptibility). This would suggest that currently defined zones of mineralization might extend into neighboring zones of deeper RTP low that might correlate to more intense areas of mineralization. Also, further zones of RTP lows elsewhere in the survey area might be prospective for similar styles of mineralization, particularly along a favourable strike direction.
The accompanying map shows a slice at 250m depth of the RTP magnetics, illustrating a pronounced and very extensive magnetic low anomaly, which largely coincides with the covered area. The two drill holes located within it were not drilled deep enough to test this anomaly, although the last 20m or so of LLA-02 contains elevated silver and bismuth assays, indicating possible proximity to mineralization.
There is no active exploration being undertaken on this property at this time.