Trial iron ore miner Freehill Mining (ASX: FHS) has unlocked further potential at its flagship Yerbas Buenas project after a geophysical survey discovered a large magnetic anomaly in the project’s northern area.
Ground magnetics were carried out in 2015 at the Chilean project, with these latest results not only validating the previous data, but offering much higher resolution.
“Uncovering this magnetic anomaly is a great development and shows the project could also be very prospective for copper and gold on top the known magnetite deposits,” Freehill chief executive officer Peter Hinner said.
“Completion of the higher resolution magnetic survey provides a significantly increased confidence level in the predictive capability of our ground magnetics to identify magnetic structures and it is becoming clearer that Yerbas Buenas hosts high quality magnetite and a magnetite structure in excess of 2.3km in length,” Mr Hinner added.
The high-resolution survey identified numerous moderate-to-strong anomalies extending from the project’s south to the north.
As a result of the higher resolution survey, Freehill said its technical team had been able to plan a much more targeted drilling campaign, which is scheduled to begin in the June quarter.
The new survey has also boosted confidence levels in the YB7 and YB3 structures and will enable Freehill to upgrade its conceptual exploration target.
“We believe the revised tonnage would be potentially sufficient for 10-15 years of mining activities in those two structures alone,” the company stated.
According to Freehill, Yerbas Buenas is close to several large magnetite deposits as well as copper and gold assets in the region.
The primary magnetic anomaly YB7 at Yerbas Buenas lies near the project’s trial mining pit where magnetite concentrate extracted in 2018 was sold to the Compania Minera del Pacifico Romeral pellet feed plant.
Freehill said this “demonstrates the high quality of pellet feed that can be derived from Yerbas Buenas magnetite concentrates.”
Meanwhile, a Davis Tube separator and XRF were used to analyse an ore sample delivered to the plant, with results generating 69.43% iron.
In addition to providing Freehill with confidence in the quality of magnetite concentrate, the agreement with Compania Minera del Pacifico Romeral gives Freehill an established offtake party with processing operations only 30km from the project.
Copper and gold potential
As well as iron ore, Yerbas Buenas could be prospective for copper and gold.
Freehill recently conducted an induced polarisation survey targeting the source of potentially significant copper mineralisation, which is common at surface in the region.
“Uncovering this magnetic anomaly is a great development and shows the project could also be very prospective for copper and gold on top of the known magnetite deposits,” Mr Hinner said.
During the December quarter, Freehill completed a drilling campaign at the project, with assays due soon.
Drilling at the project’s southern structure unearthed 15m of sand cover, followed by more than “170m of effectively continuous high-grade magnetite material”.
Yerbas Buenas is close to one of Chile’s oldest iron ore mines and encompasses 400 hectares.
The project is close to highways, cities, ports and power, with trial mining ongoing since mid-2017.