Variscan Mines discovers multiple, high-grade lenses at San Jose zinc-lead mine
Underground drilling has hit zinc mineralisation above and below mine stopes at Variscan’s Spanish mine.
Perth-based explorer Variscan Mines (ASX: VAR) has confirmed the discovery of high-grade zinc mineralisation from recent underground drilling at the central zone of the San Jose mine in Spain.
Assay results found zinc-rich, vertically-stacked mineralised lenses below areas of known mining activity at the La Caseta and 168-177 north-south trends, above and below the zone’s mine stopes.
Multiple horizons were identified with the mineralisation believed to be consistent with the stratiform-stratabound composition of sulphide orebodies in Mississippi Valley-type (MVT), lead-zinc districts.
La Caseta results
Best drilling results below the main gallery level at La Caseta underlying the known mineral trend were 16.9m at 12.5% zinc and 2% lead; and 15.6m at 3.2% zinc and 0.3% lead.
Above gallery level high-grade results included 7m at 8.3% zinc and 0.1% lead.
Variscan has since completed 20 additional holes for 400m to test the southward extent of the lower lens, with the majority of holes exhibiting “positive visual zinc mineralisation”.
Assays from the extra holes are expected in the near future.
168-177 trend assays
At the 168-177 trend, the discovery of a new mineralised lens below the main gallery level produced results of 5m at 14.2% zinc and 4.3% lead; and 5m at 11.4% zinc and 2.8% lead.
High-grade results above the gallery level included 5m at 16.5% zinc and 1.7% lead; and 4.2m at 15.4% zinc and 5% lead.
Variscan said the remainder of the mine is mostly untested at depth, providing potential for further discoveries of high-grade mineralisation, with the proximity of the lenses allowing for cumulative tonnage increases.
Major development
Variscan managing director Stewart Dickson said the discoveries were a “major development” for the company.
“It suggests significant potential for discovering additional lenses throughout San Jose as the remainder of the mine has had barely any drilling to test for lower-lying lenses,” he said.
“In aggregate, that could provide considerable scale and tonnage potential.”
He said it also reinforces the conceptual model of San Jose being a multi-layered orebody, comprising vertically-stacked, sub-horizontal, high-grade mineralised lenses of variable thickness and geometry, separated by intervals of dolostone.
This composition is similar to the nearby, world-class Reocin mine, which was considered Spain’s largest stratabound carbonate-hosted lead-zinc discovery and one of the world’s richest MVT deposits until low zinc prices in 2003 forced its closure.