The main rock types at Igor are:
- Quartzite, arenite and shale of the Chimú Formation.
- Arenite, quartzite and carbonaceous shale with syngenetic pyrite in the underlying Chicama Formation.
This sedimentary sequence has been extensively folded, thrusted and dissected by major faults. The structure is dominated by an anticline some 3 kilometres (km) long and 2 km wide. Intruding the sedimentary rocks are numerous dacitic dykes, stocks and sills that are typically altered to a phyllic hydrothermal assemblage (quartz-sericite-pyrite). Minor granodiorite is present some deep drill holes.
Precious metal mineralization at Igor consists of a series of veins, breccias and mantos principally with a north to south orientation, although secondary north-east to south-west and north-west to south-east trends are also important.
Gold and silver are the most important metals. Geochemically, there arsenic and antimony commonly accompany precious metal mineralization. Weak localised base metal (lead and zinc) mineralization is also present. Copper grades are generally low, but frequently increase with depth. Oxidation, especially along structures, is pervasive and commonly extends to depths of several hundred metres. Gold and silver mineralization appears to be Low to Intermediate sulphidation epithermal in character and there are indications of a deep porphyry copper gold system underlying the Igor District.
There are three main target areas on the project:
- Callanquitas: The most recently discovered and potentially the most important target at Igor. Mineralization consists of a series of north-south striking, structures over a zone some 900 metres long and 200 to 300 metres wide. Mineralization is open to the north, south and at depth. The December, 2012 NI 43-101 Technical Report describes this area in detail.
- Callanquitas Extension: The southern extension of the Callanquitas resource. Extensive mapping and surface rock-chip and channel sampling have defined a compelling drill target to complement the existing gold and silver resource at Callanquitas.
- Domo: A zone of bedding-parallel mantos and perpendicular veins along the crest of the southeast end of the Igor Anticline. Precious metal mineralization is controlled by a series of northeast-southwest trending faults.
- Tesoros: A system of veins, breccias and mantos along a major north-northeast striking fault that has localized the emplacement of dacitic porphyries and pebble dykes.