Drilling demonstrates significant potential at TGN’s Mulgine Trench deposit

by Leena Thomas
Mt Mulgine Project, WA Image: Tungsten Mining NL

Australian tungsten developer Tungsten Mining NL (ASX: TGN) has announced impressive results from drilling at its Mt Mulgine Project in Western Australia.

TGN reported that the drilling intersected substantial thicknesses of tungsten-molybdenum mineralisation at Mulgine Trench deposit.

Mineralised zones include 240 metres (200 metres true thickness) at 0.11% WO3, 340 ppm Mo from surface; 174 metres (155 metres true thickness) at 0.13% WO3, 290 ppm Mo from surface; and 172 metres (170 metres true thickness) at 0.11% WO3, 440 ppm Mo from 56 metres.

The company said that the drilling indicates that there is potential to substantially increase the 2014 Mulgine Trench Mineral Resource estimate.

Tungsten Mining reported that the interpretation of data is under way and a revised Mineral Resource estimate will be released in the December quarter.

Mt Mulgine project

The Mt Mulgine Project is located in the Murchison Region of Western Australia, approximately 350km north northeast of Perth.

Tungsten Mining has 100% of the tungsten and molybdenum rights on a contiguous group of tenements that have been the subject of significant previous exploration for tungsten and molybdenum.

Previous explorers had delineated two near surface JORC 2012 compliant Mineral Resources at the Mulgine Trench and Mulgine Hill deposits. Currently, there is a combined Mineral Resource of 71.0 Mt at 0.18% WO3 (0.10% WO3 cut-off) and 238ppm Mo.

PFS for Mt Mulgine

In April 2019, the Company had commenced work on a Pre-Feasibility Study (PFS) for large scale operations at the Mt Mulgine Project.

The company said that one of the outcomes of the PFS will be the declaration of a maiden Ore Reserve for the larger Mt Mulgine Project and accordingly resource definition drilling is a major component of the program.

Mulgine Trench

The company reported that the tungsten-molybdenum mineralisation at Mulgine Trench is associated with altered and quartz veined mafic and ultramafic units that form a 100 metre to 250 metre thick zone over 1.4 kilometres of strike and dips shallowly towards the northwest.

Mulgine Trench has an Indicated Mineral Resource of 0.4 Mt at 0.14% WO3 and 400ppm Mo, and an Inferred Mineral Resource of 63.4 Mt at 0.17% WO3 and 250ppm Mo (0.10% WO3 cut-off)

Drilling at Mulgine Trench

Tungsten Mining had commenced resource definition drilling at Mulgine Trench with 112 reverse circulation (RC) holes for 16,776 metres drilled to date.

The drilling program was part of the Mt Mulgine Project PFS with the objective of upgrading the dominantly Inferred Mulgine Trench Mineral Resource estimate to a dominantly Indicated status.

The company said that Phase 1 of the resource definition drilling has been completed.

Extremely encouraging results

TGN said that extremely encouraging results were received for the first 66 holes intersecting significant thicknesses of tungsten-molybdenum mineralisation within a 120 to 200 metre thick horizon over 1.4 kilometres of strike.

The company said that the drilling has confirmed its opinion that mineralisation is far more extensive than indicated by the 2014 Mulgine Trench Mineral Resource estimate.

Multiple tungsten-molybdenum intersections

The company reported that holes MMC314, MMC304, and MMC356 intersected mineralised zones with minor internal waste of 240 metres (200 metres true thickness) at 0.11% WO3 and 340 ppm Mo from surface (0 metres), 174 metres (155 metres true thickness) at 0.13% WO3 and 290 ppm Mo from surface (0 metres) and 172 metres (170 metres true thickness) at 0.11% WO3 and 440 ppm Mo from 56 metres respectively.

TGN said that the drilling has intersected significantly more tungsten-molybdenum mineralisation than predicted by the 2014 Mineral Resource estimate.

Mineralisation beneath MRE

TGN reported that, in addition to indicating better continuity to mineralisation within the Mineral Resource estimate, drilling has also intersected significant mineralisation beneath the Mineral Resource estimate.

The Company said that of the 66 holes that have received results for to date, 38 holes have intersected significant tungsten-molybdenum mineralisation beneath the block model. These holes include 40 metres (40 metres true thickness) at 0.12% WO3, 540 ppm Mo from 123 metres in MMC309; and 33 metres (29 metres true thickness) at 0.14% WO3, 270 ppm Mo from 153 metres in MMC273.

Updates and next steps

The company noted that even though holes were drilled to a prescribed depth to contain costs, a large number of the holes ended in mineralisation. TGN said that some of these will be deepened in Phase 2.

The company said that the drilling in the vicinity of the Bobby McGee gold pit encountered up to 50 metres of tungsten-molybdenum mineralisation beneath the 2014 block model.

TGN reported that the interpretation of results is underway and upon receipt of all Phase 1 drilling assays, the Company is planning to complete a revised Mineral Resource estimate for Mulgine Trench in the December Quarter.

The company said that this updated geological block model will be used to direct a more detailed drill out of the Trench deposit. It is also intended to model any accessory minerals of significance that occur within the Trench deposit.

TGN reported that it is currently undertaking a Pre-Feasibility Study on the greater Mt Mulgine Project incorporating the Mulgine Trench and Mulgine Hill deposits.

The planned activities include resource definition and infill drilling of the Trench deposit; mine design and optimisation of the mining schedule, geotechnical studies and definition of maiden ore reserves; metallurgical test work on the material from Trench; process design and engineering for the tungsten processing plant and associated non-process infrastructure; assessment of existing and exploration for additional ground water resources; and completion of native flora, fauna, aboriginal heritage surveys and regulatory approval processes.

Management comments

Tungsten Mining’s CEO Craig Ferrier commented, “The results to date justify our commitment and belief in the significant potential of the Trench deposit and the opportunity for establishing large scale mining and processing activities at Mt Mulgine.

A major focus of the PFS is understanding the polymetallic nature of the deposit and demonstrating a processing route to maximise the recovery of tungsten, molybdenum and other valuable by-products.

The very substantial widths of mineralisation intersected in this initial phase of drilling are extremely encouraging and we look forward to reporting on further results as they are received.”