JOHANNESBURG (miningweekly.com) - ASX-listed Azure Minerals' regional exploration programme over the western half of the Oposura project area, near Hermosillo, Mexico, has identified areas of strong zinc and lead anomalism and high-grade gold, silver and base metals mineralisation on the Mina Blanca Ranch prospect.
The company is planning to drill at Mina Blanca Ranch following the completion of the Oposura resource drill-out and upon receipt of the required approvals.
"Azure has undertaken the first modern exploration on the Mina Blanca Ranch in the western part of the Oposura property, and the systematic and technical approach is delivering positive results," Azure MD Tony Rovira stated.
This first phase of reconnaissance exploration comprised a gridded soil sampling programme, with samples collected at 50 m spacings along 100-m-spaced, east-west orientated lines covering an area of 1.3 km by 1.8 km within the western part of the Oposura project area.
Each sample was tested by a portable X-ray fluorescent analyser reading 35 different elements. Geochemical signatures derived from the soil sampling identified a discrete zone that was strongly anomalous in both zinc and lead, with values reaching highs of 3 195 parts per million (ppm) zinc and 1 534 ppm lead.
The anomalies for both elements are coincident, 500 m long and 250 m wide, and align along a well-defined northwest-southeast trending structural zone. Other pathfinder elements related to the Oposura style of mineralisation, including copper and manganese, also display strong anomalism coincident with these zinc and lead anomalies.
The company's geologists also inspected the historical Mina Blanca mine workings, located near the western property boundary. A single grab sample collected from the mine dump returned high grade assays for gold at 1.71 g/t, silver at 1 568 g/t, copper at 4.63%, zinc at 2.81% and lead at 1.60%.
The Mina Blanca workings host a vertically-dipping, north-south-striking, structurally-controlled style of mineralisation, which is very different from the horizontal, carbonate-replacement style of the Oposura deposit.
The old mine workings are situated within coincident soil anomalies for zinc, lead and other pathfinder elements. Results from this early-stage exploration indicate that additional precious and base metals mineralisation may be present within the western part of the Oposura property and further exploration, including drilling, is warranted.
When the Oposura resource drill-out has been completed, the company's focus will shift to an expansionary phase to test for repetitions and extensions of the high-grade Oposura massive sulphide deposit, and to explore for new styles of mineralisation like that identified at Mina Blanca.
Azure bought 100% interest in the Oposura prospect for $1.5-million in August last year.