FRAMBOID-DERIVED STRUCTURES IN SOME TASMAN FOLD BELT BASE-METAL SULFIDE DEPOSITS, NEW-SOUTH-WALES, AUSTRALIA

Base-metal sulphide deposits within the Tasman Fold Belt, New South Wales, Australia, contain a range of pyrite textural types which suggest textural evidence for the transformation of framboidal pyrite into pyrite atoll structures in a variety of sulphide and non-sulphide matrices. The writers suggest that the textural transformation occurred while the sulphidic sediments existed as colloids (gels), rather than by growth in the solid state. The resulting conceptual model provides a scheme for the explanation of a wide variety of sulphide textures in these deposits, and also for comparison with similar textures in other sulphide deposits of related ore genesis.