Mirador Copper-Gold Porphyry Deposit, Ecuador
The Mirador copper-gold deposit is located within the eastern foothills of the Andes in southeast Ecuador, 340 kilometres south of Quito. Mean elevation is 1000m.
Mirador lies at the south end of a 40 km long, north-south belt of porphyry Cu (Au) and Cu deposits, discovered in the mid 1990s and since called the Corriente Copper Belt. At a 0.4% copper cut-off, the 142 drill holes (36,284 metres) outline measured and indicated resources of 438 MT of 0.61% Cu and 0.19 g/t Au, and inferred resources of 235 MT of 0.52% Cu and 0.17g/t Au.
The deposit is hosted by Late Jurassic granite and porphyry of the Jurassic calc-alkaline Zamora batholith, of the Abitigua Subdivision. Radiometric dating suggests copper mineralisation is associated with the younger Late Jurassic porphyry intrusive phases of the Zamora Batholith with ages of 152 to 157 million years.
Geology at Mirador consists of potassic altered and mineralized granite intruded by early, also-mineralized feldspar-hornblende porphyry and a central hydrothermal breccia pipe, which in turn are intruded by barren, post-mineral porphyries and hydrothermal breccia. These units are unconformably overlain by Cretaceous Hollin Formation platform quartz arenite. Mineralization is primarily finely disseminated hypogene chalcopyrite, with locally significant chalcocite enrichment.
Copper, Mirador, Ecuador, Porphyry, Gold