The La India Project is 100% owned by Metals Exploration, following its acquisition of Condor Gold, which was completed on 15 January 2025.
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Summary:
Gold mineralisation at La India occurs associated both with quartz vein systems and within well-confined hydrothermal breccias. The veins and stockwork zones are hosted within massive andesites, andesitic and felsic tuffs or felsic lava flow deposits. Veins are typically less than 3 m in width, but stockwork zones and stacked stockwork-vein zones can be up to 25 m wide.
Quartz veins, often including a brecciated component, vary in thickness and are most typically between 0.7 m and 2 m in thickness. In many areas, the wallrock hosts a breccia or stockwork zone with vuggy quartz veinlets up to 5 cm thick and accounting for up to 70% of the rock mass. The breccia/stockwork zone is typically up to 10 m thick and is associated with silica-haematite alteration. The quartz in the breccia zone may be gold mineralised, although the country rock component means that gold grades are diluted compared to the veins.
The grade of gold and silver can vary from a few grams per tonne to significant intersections with grades in excess of 30 g/t Au (>1 oz/t). Gold mineralisation occurs as fine gold-silver amalgam with a gold to silver ratio of 1 to 1.5.
The La India property includes the La India, America, Central Breccia and Mestiza, Cacao deposits.
Gold mineralisation within (Cacao) and on the edge (Central Breccia) of the Sebaco Graben is hosted by a thick andesite unit which is more susceptible to alteration. At these zones a proximal kaolinite-pyrite (argillic/ acid sulphate) alteration locally occurs around the veins in both Central Breccia and Cacao. A medial sericite alteration is recognised forming a halo a few metres around the vein at Cacao. This gives way to distal smectite-calcite-pyrite alteration at higher levels and chlorite-calcite-pyrite (propylitic) alteration at deeper levels.
La India
New diamond core drilling completed in 2020-2021, along with re-logging of previous drill core and mapping of new surface exposures, has allowed a more robust geological (lithological and structural) model of the La India deposit to be developed.
The La India Vein Set comprises two cross-cutting structures, comprising the NW striking La India structure (previously referred to as the India-California structure) and EW striking Teresa-Agua Caliente-Arizona veins.
The majority of the mineralisation is hosted by the La India structure. The La India structure is a normal fault striking 330° and dipping ENE which can be traced at surface along a strike length of approximately 1,550 m.
The mineralised vein does not reach surface further to the southeast, apparently downthrown by the orthogonal Highway Fault. However, it has been traced with drilling a further 350 m along strike below surface, beyond which it remains open along strike at depth. The La India structure displays evidence of trans-tensional movement with a sinistral transverse component inferred.
In the hangingwall zone, several steep-dipping veins have formed in contact with the main structure that are interpreted as tension gash fill.
America Mine
The gold mineralisation at America occurs along the faulted contacts which separate three structural blocks. The America-Escondido structure forms two of the three recognised block boundaries. The structure is characterized by a 60° bend between the America fault which strikes 300° and dips approximately 55° to the northeast and the Escondido fault which strikes north and dips at approximately 45° to the east. Both the America and Escondido fault limbs are planar normal faults, typically 1-3 m wide and characterized by the development of sand to gravel-grade cataclastic textures on the principal fault plane and small, metre-scale tension gashes in the hangingwall. A wider quartz breccia has developed at the flexure zone. The Constancia veins are hosted by a steeper dipping structure striking at 270-290° and dipping at approximately 70° to the north.
Central Breccia
The Central Breccia is a multi-stage hydrothermal breccia deposit with low grade gold mineralisation is associated with carbonate breccia cement and high-grade gold mineralisation is associated with argillic alteration and sulphide mineralisation, hosted by a massive porphyritic andesite located at the centre of the graben-like structure that runs down the axis of the America Vein Set near the intersection with the regional cross-cutting NE-Fault. Drilling has shown that the andesite overlies a felsic pyroclastic breccia. Two stages of hydrothermal breccia development are recognised, an early hydraulic breccia with evidence of clast movement and rotation and a silica-cemented microbreccia matrix, and a later crack and fill brecciation with calcite-cement containing anomalous gold values formed under a more passive dilational regime.
Gold mineralisation is associated with a later calcite and quartz calcite crack and seal breccia. The breccia typically has grades of 0.1 to 0.2 g/t Au, within which high-grade zones (interpreted as shoots within the wider breccia pipe) typically over 10 m thick and grading between 2 g/t and 7 g/t Au occur. The high-grade zones are often associated with sulphide minerals and intense argillic alteration and quartz veins.
The gold-silver mineralised phreatic breccia and associated clay alteration (acid sulphate) at the Central Breccia, and the outcropping sinters and strong proximal sericite grading through to medial smectite and distal chlorite-calcite-sulphide (propylitic) alteration at Cacao is consistent with near surface hydrothermal mineralisation at the top of a low sulphidation epithermal system. This observation is consistent with their locations within a downthrown graben and borne out by the observations of classic low sulphidation banded gold-silver mineralisation encountered in drilling more than 200 m below surface at Cacao.