Skip to main content
Conference Proceedings

1987 AusIMM New Zealand Branch Annual Conference

Conference Proceedings

1987 AusIMM New Zealand Branch Annual Conference

PDF Add to cart

Alluvial Platinum in the Howard Valley, Nelson Lakes Area - Origin and Comparison with Some Other New Zealand Platinum Occurrences

Alluvial platinum was recovered during gold mining operations in Maud Creek, a tributary of the Howard River. Average electron probe analyses give Pt 88.75, Fe 5.27, Ir 0.70, Os 1.06, Pd 0.34, Ru 0.14, Rh 1.29, Cu 1.06. Rare grains of a Pt-Fe-Cu alloy are also present and an unusual feature of all grains is the relatively high rhodium content which finds expression in segregations of rhodium arsenide, cherepanovite. Platinum is found in the Orepuki area of Southland, where it is probably partly derived from the mafic rocks of the Longwood Complex. Rocks of the Rotoroa Complex, similar to those of the Longwood Complex, form bedrock in Maud Creek and are possibly the source of the Howard platinum. Alternatively, it might be derived by glacial transport from the Matakitaki ultramafic block 30 km to the southwest. Origin from the Rotoroa rocks is preferred as, if the Matakitaki rocks are part of the Dun Mountain Ophiolites, they might be expected to contain osmiridium rather than platinum._x000D_
The ratio Pt:Ir-Os has been widely used to distinguish low Pt:Ir-Os ophiolitic from high Pt:Ir-Os gabbroic assemblages. Mafic complexes such as Longwoods, Darran, Rotoroa, and Riwaka might be expected to show similar highPt:Ir-Os ratios and be targets for platinum exploration. Detrital platinum examined from the Parapara area, Golden Bay is mainly osmiridium, with rare grains of rutheniridosmine, very similar in composition to that found in concentrates from the Kaniere dredge, West Coast.
Return to parent product
  • Alluvial Platinum in the Howard Valley, Nelson Lakes Area - Origin and Comparison with Some Other New Zealand Platinum Occurrences
    PDF
    This product is exclusive to Digital library subscription
  • Alluvial Platinum in the Howard Valley, Nelson Lakes Area - Origin and Comparison with Some Other New Zealand Platinum Occurrences
    PDF
    Normal price $22.00
    Member price from $0.00
    Add to cart

    Fees above are GST inclusive

PD Hours
Approved activity
  • Published: 1987
  • PDF Size: 0.822 Mb.
  • Unique ID: P198712022

Our site uses cookies

We use these to improve your browser experience. By continuing to use the website you agree to the use of cookies.