Colombia-focused explorer Los Cerros (ASX: LCL) confirmed an extended drilling campaign has intercepted thick gold mineralisation from surface at the Tesorito target which sits within the Quinchia project in the country’s rich Mid-Cauca gold belt.
The first diamond hole at the southern Tesorito anomaly returned an “exceptionally wide” intercept from 230m grading 1 gram per tonne gold from surface, including 18m at 2g/t with 6m at 4.1g/t from 6m.
Assays also returned 116m at 1.38g/t gold from 114m, including 74m at 1.6g/t from 114m with 4m at 3.18g/t; and 2m at 9.58g/t from 176m, within 6m at 4.86g/t from 174m.
Gold mineralisation exceeding 1g/t has now been demonstrated by three separate diamond holes to exceed 230m downhole thickness, over an area of 300m by 250m and remaining open in all directions.
Results from the other holes were 384m at 1.01g/t gold from 16m, including 29.3m at 1.9g/t from 136.75m; and 253.1m at 1.01g/t gold from 2.9m, including 64m at 1.67g/t from 144m.
A significant new development has been the presence of primary bornite, banded veining and anomalous copper – all of which indicate an increased potential for copper mineralisation to develop at depth.
The geology is believed to be typical of the core of many porphyry copper-gold deposits along the Mid-Cauca belt, including the multi-million ounce Nuevo Chaquiro deposit owned by AngloGold Ashanti (ASX: AGG), located 51km to the north of Quinchia.
The drill rig is currently testing the northern part of the Tesorito target, located 200m from the first hole, where a previously undrilled zone of anomalous gold and molybdenum in soils occurs concurrent with a magnetic high.
It will then return to south to further test extensions to the higher-grade porphyry core laterally and at depth.
Los Cerros said future holes will focus on determining Tesorito’s strike, width and depth continuity.
Managing director Jason Stirbinskis said results from the first hole at Tesorito demonstrate the potential for deeper extensions of gold-copper porphyry and near-surface, high-grade epithermal gold at Quinchia.
“This is a highly encouraging start to our drill campaign as it provides a sense of near-surface porphyry mineralised volume given similar results of nearby holes, and also hints to further potential at depth,” he said.
“Primary bornite is a copper-rich mineral species and its presence, based on visual logs, correlates to elevated copper in assays which has raised the possibility of more copper occurrences as we chase depth extensions in subsequent drilling.”