Metminco Limited (ASX: MNC), soon to be renamed Los Cerros Limited, has announced a highly encouraging update on the ongoing drilling at the Chuscal Gold Target of Quinchia Gold Project in Colombia.
The company reported that the first hole of the maiden Chuscal drilling program, CHDDH001, ended at 452m depth, delivering significant gold mineralisation.
MNC said that CHDDH001 passed through an extensive 350-metre-wide mineralised zone from surface carrying an average uncut grade of 0.57 g/t gold over this extensive interval.
Metminco reported that a number of intervals with higher grade gold and silver were intersected within the broader 350m zone.
The company reported that the second hole (CHDDH002) was completed at 412.4m and assays are awaited. Meanwhile, the drilling of the 3rd hole (CHDDH003) is in progress and expected to be completed by end of November, with assays due in mid-December.
MNC’s Quinchia gold project is located in central west Colombia, 100km south of Medellin. The Quinchia Portfolio covers 10,542Ha consisting of granted titles and applications and includes deposits and targets such as Miraflores, Chuscal, Dosquebradas, and Tesorito.
Metminco is earning a 51% interest in the Chuscal Gold Prospect from Anglo Gold Ashanti Colombia SA.
Drilling at Chuscal
MNC had recently commenced drilling at Chuscal prospect. This is one of the first drill campaign ever conducted at Chuscal.
Metminco said that it had prioritised the drilling of Chuscal Prospect as a result of its expansive 900m by 530m surface gold anomaly averaging 1.76 g/t Au (uncut), channel sampling of epithermal veins exposed in the Guayacanes artisanal workings which averaged 8g/t Au including a continuous along strike zone of 83m @ 7.3g/t Au4, and favourable geology – suggesting potential for Chuscal to be a very significant deposit for the company.
Impressive drill results from CHDDH001
The company said that the maiden hole (CHDDH001) was designed to test the NE flank of the Guyacanes diorite which hosts artisanal underground workings; and to test a magnetic low geophysical anomaly flanking this to the north.
Metminco said that CHDDH001 reported significant gold values to 350m of the 452m deep hole with mineralisation occurring in monzonite, diorite and breccias (hydrothermal, crackle and magmatic breccias). The company said that CHDDH001 carries an average uncut grade of 0.57 g/t gold over this extensive interval.
Metminco announced that a number of intervals with higher grade gold and silver were intersected within the broader 350m zone, including 6m @ 2.52 g/t Au and 10.25 g/t Ag from 0m to 6m, including 2m @ 5.56 g/t Au and 29 g/t Ag from surface, 22m @ 1.22 g/t Au and 0.50 g/t Ag from 10m to 32m, 54m @ 0.81 g/t Au and 0.63 g/t Ag from 56m to 110m, 2m @ 3.09 g/t Au and 0.77 g/t Ag from 222m to 224m, 2m @ 6.44 g/t Au and 87.40 g/t Ag from 324m to 326m, and 8m @ 2.82 g/t Au and 29.96 g/t Ag from 342m to 350m.
MNC said that the first hole provides critical information for understanding the broader mineralising system and supports the exploration model of a high temperature porphyry-related gold event being locally overprinted by lower temperature epithermal (ISS) vein gold.
Drill hole CHDDH002
The company announced that the second hole CHDDH002 was drilled to test the eastern end of the large surface geochemical anomaly and pass underneath the historic Guayacanes workings to investigate the core of the diorite zone as mapped on surface.
Metminco said that hole CHDDH002 was completed at 412.4m cut across the Guyacanes diorite and encountered considerable brecciation before ending in monzonite, all of which contained local ISS veining to varying degrees.
The company said that porphyry style potassic alteration was noted around 260m. MNC announced that assays are awaited for CHDDH002.
Drill hole CHDDH003
Metminco reported that the rig has now begun drilling CHDDH003. The company said that the drill hole CHDDH003 lies some 500m north-northwest of CHDDH002 and will test the Corporacion diorite on the NW end of the gold soil anomaly and is orientated to intercept several of the inferred “horsetail” structures.
The company said that the 350m hole is expected to take the remainder of November with results due mid-December.
Latest updates and next steps
The company announced that the preliminary drill program consists of approximately 2,400m in 6 to 8 holes to evaluate the geology, alteration and mineralization styles along the Chuscal trend. As a maiden drill program, the project information obtained during the drilling will be used to refine the Exploration Model providing a more resilient base for decision making.
MNC said that the objective of the program is to provide a guide to the mineralization potential of the system, both in terms of potential grade and volume, to guide resource targeted drilling in a second phase drilling program.
Metminco’s Managing Director, Jason Stirbinskis commented:
“This is a remarkably strong result on our first hole given the extent of the mineralisation encountered from surface, and it has proven very illuminating, greatly improving our understanding of the geology.
After outstanding drill success last year at the nearby Tesorito porphyry discovery, including a best result of 253.1m @ 1.01 g/t Au from surface, including a higher grade zone of 64m @ 1.67 g/t Au4, and now hitting this wide interval at Chuscal, we believe we are in enviable porphyry territory.
It remains early days into our drilling at Chuscal, but this first intersection has certainly provided very strong encouragement about what Chuscal could be when you consider the sheer scale of the gold anomaly at surface, the impressive widths of mineralisation encountered and its location in the heart of the Mid-Cauca belt, which is already host to several multi-million ounce porphyry and epithermal deposits.
When compared to other global porphyry systems and recent discoveries, this early result reaffirms our view that our Quinchia Project and Chuscal in particular, have great potential”.
“As this is the first drilling campaign at Chuscal, our understanding is evolving dramatically with every few meters drilled. What we can say so far, is that we are confident we are seeing overprinting gold events that have the potential to introduce, remobilise and enrich the gold grades and, under the right conditions, could generate significant high grade zones within a much larger lower grade region, such as those discussed above.
The extensive gold event with a higher temperature porphyry signature is providing a large lower grade gold backdrop and, based on alteration signatures observed (potassic alteration), suggest there may be a porphyry source close by.
We also see vein gold cutting though most rock units. These ISS veins are more localised and preliminary interpretations suggest may be associated with a dilatational “horsetail” fault structure that is inferred in the area.
The deeper half of hole CHDDH002, which tested the Guayacanes veins (assays pending) and CHDDH003 will no doubt tell us much more about the role of the structures and source of the gold in the project”.