Cummins Range Platinum

View Cummins Range Magnetic Image

Navigator is targeting the Cummins Range diatreme for platinum group metals (PGM), which have not previously been evaluated.

The Cummins Range diatreme consists of a carbonatite-rich core that is surrounded by pyroxenite. The central core contains an inferred resource of 6.3Mt at a grade of 0.5-1.0% rare earth oxides (CRAE mid 1980's).

Recent research has recognised two aspects favourable for PGM:-

• the presence of sulphide-rich (10%) pegmatoidal pyroxenite rocks in the central core of the diatreme, and
• anomalous gold mineralisation grading up to 0.4g/t gold in several shallow auger holes within the outer pyroxenite zone.

The targeted style of platinum group mineralisation has analogies with Ural-Alaskan and Onverwacht style pipes, which represented the world's primary source of platinum group metals prior to the discovery of the giant platinum resources of the Bushveld and Norilsk layered igneous complexes.

Platinum group metal grades associated with syn-magmatic volatile deposits can be high, although published resource and production data are more limited as several deposits were mined in the 1920's. Examples include: -

Onverwacht (Bushveld)
Central core averaged 34 g/t PGM; mined in 1920's

Driekop (Bushveld)
Estimated grade of 20-30g/t PGM; tonnage potential 125,000oz to 200m; mined-out core 25m in diameter; mined in 1920's

Salt Chuck (Alaska)
300,000t @ 26.1g/t Pt and 14.9g/t Au

Nizhny Tagil Massif (Urals)
Average grades 15-20g/t PGM

A detailed aeromagnetic survey has also outlined several other discrete magnetic features in the Cummins Range area that are prospective for PGM, diamonds and rare earth oxides.