Estrella launches geophysics on high-grade Timor-Leste manganese hits

Estrella Resources has reported further significant manganese intersections from ongoing drilling at its Ira Miri prospect in Timor-Leste. 

The work is targeting secondary manganese mineralisation just below the surface, building on previous high-grade finds west of the initial discovery area. 

Four recent drill holes penetrated visible primary manganese and secondary enrichment. The company expects to receive verification assays from the holes in four to six weeks. 

Visible estimates from the drilling include a best hit from the four holes of 2.5 metres, estimated at 70 per cent manganese oxide from 1m depth. The second-best grade run was 3.1m of visually estimated 60 per cent manganese oxide from 1.4m depth.

A third hole bored through a 1.6m run estimated at 30 per cent manganese oxide from 1.4m, while another hole delivered 0.8m at about 15 per cent manganese oxide from 7.8m depth. 

The secondary enrichment follows the trend of primary manganese in the Noni Formation, which runs generally northwest, despite some small-scale deviations due to folding. Drilling will continue to test along strike in the supergene horizon between two main outcrop areas.

Estrella has planned a large airborne geophysical survey program to improve geological models and drill targeting across its manganese and limestone prospects in Timor-Leste. That work has now started at Ira Miri, covering a 4.2 kilometre by 3.5km area, with LiDAR and drone-based magnetics surveys underway.

The LiDAR provides high-resolution surface imagery and topographic data to provide positional control of the magnetics and upcoming MobileMT surveys. MobileMT is an airborne electromagnetic tool that uses natural geophysical fields to map subsurface resistivity, helping to spot geological features from near-surface down to over a kilometre deep. 

Estrella Resources managing director Chris Daws said: “It is comforting to see more manganese intersected in the current drill program at Ira Miri, expanding on the already exceptional initial manganese assay results recently returned.”

A 200-hectare core area at Ira Miri will be covered by a drone-borne magnetic survey at 50m line spacings for a total of 53 line-kilometres.

LiDAR and MobileMT will cover a surrounding 1500ha area at the same line spacing for 300 line-kilometres. Combined, the two surveys are expected to help identify additional primary and secondary manganese drill targets.

Estrella has already completed a LiDAR survey at the company’s Werumata limestone project to support its resource planning and development. Access roads and drill sites at the project have been finalised, and community consultations wrapped up with a local cultural ceremony.

Estrella has submitted an environmental application to support its planned site preparation and drilling, and the company is awaiting approvals. 

The program is slated to entail an initial 27 reverse circulation (RC) holes as well as stratigraphic diamond drilling, to be followed by further infill RC work for a JORC-compliant resource. 

Once approved, a crew will build all-weather access to handle the imminent wet season. 

Quotes are also being received for a coastal bathymetric survey to assess shipping-port options for potential calcite exports. Estrella expects to make a decision shortly.

Step-out drilling at Ira Miri is continuing while Estrella waits on the Werumata approvals, after which the rig will move back to Dili for reconfiguration to an RC drill string in preparation for evaluating the limestone. The company also needs to prepare enough drill pads in the rocky terrain before the rig begins work .

Estrella's steady progress at Ira Miri and Werumata demonstrates a balanced approach to building out the company’s Timor-Leste assets. The assays will be its next confidence-building step. 

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