TNM Drill Down: South America dominates Top 10 copper assays YTD

Building on our popular weekly TNM Drill Down feature ranking the best gold assays of the week, The Northern Miner presents the top 10 drill results for major metals year to date. We start with the best copper assays for the year to Aug. 1, 2023. Drill holes are ranked by copper grade x width, as identified by data provider Mining Intelligence.

 

Filo Corp at Filo del Sol

Filo Corp‘s (TSX: FIL) prefeasibility-stage Filo del Sol project in San Juan, Argentina, produced the highest width x grade value among copper explorers so far this year. On Jan. 10, the Vancouver-headquartered company reported that hole FSDH071 cut 1,028 metres grading 0.78% copper for a width x grade value of 801.84 at Filo del Sol.

This included a segment of 172 metres with an exceptionally high concentration of 2.14% copper equivalent from 408 metres and another segment of 237.5 metres with 1.49% copper equivalent from 776 metres. The drilling ended at a depth of 1,320 metres due to equipment limitations, with the final 20 metres averaging 0.46% copper equivalent.

The company reported the result alongside hole FSDH070A, with both holes drilled in the Aurora zone, but FSDH070A being about 410 metres away, further demonstrating the project’s exploration potential.

As of Jan. 18, Filo del Sol hosts indicated resources of 432.6 million tonnes grading 0.33% copper for 3.2 million lb of metal. The inferred resource stands at 211.6 million tonnes grading 0.27% copper for 1.3 billion lb of metal.

Nine rigs are active on the project, and winter activity focused on Aurora infill and the Aurora-Bonita gap drilling.

Atex Resources at Valeriano

Atex Resources (TSXV: ATX) produced the second-best copper assay this year to date. The company reported on March 30 that hole ATXD-11B cut 1,342.5 metres grading 0.46% copper for a width x grade value of 617.55 at the advanced exploration-stage Valeriano project in Chile. Results from ATXD-11B confirm a new high-grade porphyry trend called the Western Trend. The company interprets the results as expanding the mineralized corridor over 300 metres west of the Central High-Grade Trend and is open along strike for further extension.

ATEX CEO Raymond Jannas said at the time the results from ATXD-11B were a “step change” in demonstrating the growing scale potential at Valeriano.

Most recently, the company reported on Jul. 13 it had completed holes ATXD-24 and ATXD-22B, the last two holes, from its third phase of drilling. “Hole ATXD-24 is a very significant hole as it intersected Early Porphyry further west than anticipated demonstrating that the Central Trend is wider than anticipated in this area. We look forward to completing this hole in the fall and are especially excited to follow up and test the continuity of this wider part of the Central Trend,” said Jannas in a release.

The company is compiling a resource update for Valeriano, due by September, which will underpin plans for the fourth drilling phase to start in October.

Aldebaran at Altar

This year’s third-best copper assay comes from Aldebaran Resources (TSXV: ALDE). On May 31, the company reported that hole ALD-23-225B returned 1,056 metres grading 0.51% copper from 291 metres depth for a width x grade value of 538.66 at its preliminary economic assessment-stage Altar copper-gold project in San Juan province, Argentina.

The company said then the hole was among the best holes completed at the Altar project in terms of grade and length.

Hole 225B infills a 400-metre gap between previous drill holes 223 and 224, which also returned long runs of attractive grades, further confirming the continuity of the new Altar United mineralized zone. Significantly, the holes encountered higher-grade mineralization than the average copper-equivalent grade in the current resource, suggesting that the company may have found a “hot spot” within the more extensive system, Alderaban said.

As of Mar. 22, 2021, Altar held measured and indicated resources of 1.2 billion tonnes grading 0.43% copper for 11.4 billion lb of metal. It has another 189.2 million tonnes grading 0.42% copper for 1.8 million lb copper inferred.

On August 14, the company announced it had earned a 60% interest in Altar from Sibanye-Stillwater (NYSE: SBSW; JSE: SSW). It has also given Sibanye notice that it intends to proceed with the second option to gain 80% ownership by spending a further US$25 million over 3 years. Aldebaran had since 2018 spent US$38 million on the project.

The company was last actively drilling with four rigs but had now shut down operations for the winter, with holes ready to re-enter during the next field season.