Mineralized Zones
The Camino Rojo deposit comprises intrusive related, clastic sedimentary strata hosted polymetallic gold, silver, arsenic, zinc, and lead mineralization.
Three stages of mineralization, including two styles of high-grade gold-silver mineralization, have been observed in the Camino Rojo deposit:
• Stage 1 K-metasomatism (adularia)-pyrite – K-metasomatism with disseminated pyrite replaced the mudstone, siltstone and fine-grained sandstones in the Caracol Formation. Mineralization is typically low-grade gold with 0.1- 0.4 g/t.
• Stage 2 Intermediate Sulphidation (“IS”) veins – IS veins with pyrite-arsenopyrite-sphalerite±galena, calcite and minor quartz. Moderate to high grade gold (0.4 to +4.0 g/t), high zinc grades (0.5 to >2.0% Zn) and high values of As, Pb and Ba, with variable Ag.
• Stage 3 LS veins – colloform banded quartz veins, drusy-coxcomb quartz veins, and quartz-cemented, polymictic hydrothermal breccia with pyrite-galena-sulphosalts, adularia and electrum. Moderate to high gold grades (2.0 to 15.0 g/t) with high silver (100 to 500 g/t), and high As and Sb values, but variable to low Zn, Pb, and Ba values.
At hand specimen scale, mineralization is controlled by bedding and fractures. The sandy and silty beds of the turbidite sequences of the Caracol Formation are preferentially mineralized, with pyrite disseminations and semi-massive stringers hosted within them, presumably due to higher syn-mineralizing ........
