|MadSci Network: Earth Sciences|
The short answer is yes: aluvial platinum deposits from decomposed serpentine (which is also high in auriferous ores such as nickel, gold, copper, cobalt and chromite), make up the Central Queensland Kanuna field. However, experience has indicated some rocks poor in Chromite have higher valus of Platinum.
I live in Mt Morgan which was once the worlds biggest body of gold and copper. Though the mine did not produce Platinum, the nearby river Dee has aluvial platinum and gold found together a the top of the river system.
Reference: 1920 B Dunstan, Qld Government Geologist Reports on Mineral Fields.
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