Consolidated Zinc Limited (CZL: ASX) has announced a highly positive update on the regional exploration of its Plomosas project in Mexico.
The company reported that mapping has identified additional mineralised structures to the north of La Chona and Enrique Vein Systems, related to large structural lineaments.
Highlighted rock chip results from the La Chona and Enrique areas include 6.21 g/t Au, 4.75 g/t Au and 3.39% Cu, 3.32g/t Au, 2.32 g/t Au and 1.45 g/t Au.
The company said that the reconnaissance mapping and soil and channel sampling confirmed that gold is widespread in the system within the Plomosas concessions.
Plomosas project
CZL’s 100%-owned high-grade Plomosas Zinc Project covers more than 3,000 hectares in the northern Mexican state of Chihuahua, approximately 350km from Mexico’s border with Texas. Plomosas is in an area with an extensive history of development in base metal operations.
Historical mining at Plomosas between 1945 and 1974 extracted over 2 million tonnes of ore grading 22% Zn+Pb and over 80g/t Ag.
Regional exploration program
Within Plomosas, the company had commenced exploiting the potential of the high-grade Zinc, Lead, and Silver Mineral Resource through the identification, exploration, and exploitation of new zones of mineralisation within and adjacent to the known mineralisation with a view to identify new mineral resources that are exploitable.
The exploration work completed in the north of the concessions was to confirm previous assay results, ground truth interpreted structures, and understand the geological setting for any gold mineralised systems.
The work was completed to expand on the known data and discover additional structures that may be host to gold mineralisation.
CZL reported that several prospective locations have been identified from the regional work, which includes Potrero, Alfonso, Alfonso Extension, José, and Javier. This is in addition to the La Chona, La Chona ext, and Enrique within the La Chona-Enrique trend.
Widespread high-grade gold identified
The company said that the prospect areas to the north west of Plomosas are prospective for gold as the area has undergone structural brittle deformation resulting in auriferous quartz, hematite veins containing variable copper mineralisation and related alteration occurring during deformation.
CZL said that the confirmed presence of intrusive granite to the north may be the driver for any potential mineralisation occurrence in the Don Lucas concession, which includes the La Chona-Enrique trend.
La Chona and Enrique areas
La Chona-Enrique is located approximately 5km to the west-northwest of the Plomosas Mine and within the Don Lucas Concessions area.
Exploration has proven that the two areas of La Chona and Enrique that are located approximately 420m apart, occur on similar structures that maybe offset by north-eastern faults.
CZL said that to the north of the La Chona-Enrique trend, several additional sub-parallel north-westerly trending structures have been identified comprising quartz veining with hematite and copper mineralisation.
High-grade assays
The company announced that significant assays that were returned from this campaign of exploration. The rock chip samples from outcrops returned high-grade results of 6.21g/t Au (sample 26260), 4.75g/t Au, 3.39% Cu (sample 26262), 3.32g/t Au, (26264), 2.32g/t Au (26214) and 1.45g/t Au, 0.64% Cu
CZL noted that previous high-grade results may represent plunging gold shoots which are formed at the intersection of structures along the main La Chona Enrique trend.
No significant results from other prospects
The company reported that rock sampling from other prospects, Alfonso, Alfonso Extension, Jose, and Javier returned no significant results from analysis.
Alfonso is hosted in Paleozoic Limestone and in the basement sequence of the Plomosas Formation, while the José and Javier area is hosted in the upper section of the Plomosas Sequence, which is described as sandstone-breccias.
The company said that no further work is planned at this time for these areas.
Updates and next steps
CZL reported that the La Chona-Enrique mineralised trend occur on a defined lineament that is cut by several north-westerly trending structures. The company said that these structures may host gold shoots that are high grade, steep in orientation and the tonnage potential needs to be investigated.
Consolidated Zinc reported that further exploration is planned to develop the interpretation of the mineralised systems. The company said that the discovery of additional mineralised systems to the northeast and parallel to the La Chona-Enrique trend opens up the area and warrants further exploration to identify high grade shoots.
Consolidated Zinc said that the future exploration work will define all targets to the extent required to identify the highest priority targets to be drilled for resource definition and then studies to assess the commercial viability of the gold for exploitation.
The company reported that the exploration will continue to focus on the La Chona-Enrique system and along the extensions that occur in the northwest. The La Chona-Enrique system may widen to the northwest and follow up exploration will test on-strike extensions.
Assessing Potrero project
CZL said that the Potrero project will also be assessed in the next exploration campaign. The company said that it is currently establishing contact with landholders to discuss access for exploration within the Don Sebastian Concession as well as landowners to the immediate north of the Concession area.
The Potrero project is considered highly prospective and a high priority due to the presence of intrusive felsics and highly deformed host rocks, along with coincident high-grade results from historic workings which returned values up to 14.65g/t Au.
The company said that the exploration will be focussed on the +3km strike length of exposed felsic intrusives in this area.