Loica Project


The Loica Project covers an area of 35 square kilometres and is located approximately 100 kilometres to the southeast of Ovalle, 30 kilometres south of the Mollacas Project, and occurs at an altitude of 2,000 to 2,800 metres above mean sea level.


The Loica-Victoria area comprises a hydrothermal alteration system measuring 5 by 2.5 kilometres, which hosts a "porphyry copper" style of mineralisation.  The deposit is related to a dacitic porphyry which has intruded volcanic and volcaniclastic rocks of the Vinita Formation. The outcropping lithological units have been mapped, and indicate the presence of a large hydrothermal alteration system with a potassium silicate nucleus surrounded by an extensive envelope of quartz-sericite altered rocks, which are in turn enclosed within a propylitically altered halo.

Mineralisation is found to be quite diffused at the surface and has been weathered to form copper oxides.  The most anomalous areas are located at the central sector of the dacite porphyry, and in the contact zones between the porphyry and the andesites, including a belt of intrusive breccias, which extend in a northerly direction.  The mineralisation is clearly related to the Loica porphyry and the resulting potassic and quartz-sericitic alteration.

As the porphyry system has been subjected to significant erosion that has exposed the potassic altered core, the dominant mineralisation style is likely to be that of a hypogene sulphide type, concentrated in hydrothermal breccias.

Exploration Results

Earlier exploration programs comprised regional mapping and rock-chip geochemistry (1965)  which highlighted the close relationship between the lithologies of interest (dacite porphyry and hydrothermal breccias), hydrothermal alteration (potassic and quartz-sericite) and anomalous copper and molybdenum occurrences.  An Induced Polarisation and resistivity geophysical survey was also undertaken at the time, which delineated an arcuate zone with a relatively high chargeability, coincident with the concentric transition zone between the quartz-sericite and propylitic alteration zones (viz. pyrite halo).

Over the period June 2006 to early 2007 Minera Hampton Chile Limitada (a wholly owned subsidiary of Metminco), completed 8 inclined Reverse Circulation drill holes (4,426m) and 3 inclined diamond drill holes (2,001m).  All of the drill holes intersected low grade mineralisation over large drill intercepts within a depth range of 0 to 659 metres.  The the best results were returned for drill hole LR 07 (Reverse Circulation) located near the core of the porphyry system (32 metres at 0.36% Cu and 128ppm Mo).

Future Work

A exploration program is planned to establish the lateral and depth extents of the porphyry system using deep-penetrating geophysical methods and a staged diamond drilling program, in order to assess the tenor of the porphyry style mineralisation at greater depths than those tested to-date.