Ann: Geophysical IP Anomolies Halls Peak , page-5

http://www.smedg.org.au/AustSedexZnPbAg.htm

Australian Sedex Deposits are code words for fine-grained sediment–hosted Pb-Zn-Ag deposits of mid-Proterozoic age which may or may not be exhalative and which are best developed in the Mt Isa Inlier and McArthur Basin regions of northern Australia.

One could also include in this classification the Broken Hill Pb-Zn-Ag deposit type which is also of mid-Proterozoic age and is arguably of sedimentary-exhalative origin, but differences between the “Isan” type and “Broken Hill” type of deposits are sufficient to warrant their separate treatment.

By any standards, these are major accumulations of metal – average size is about 100mt @ +10% Pb+Zn; direct shipping grades of +50% Pb+Zn are present at Lady Loretta locally, and Ag credits range from 35g/t at Century, 60g/t at HYC to 100 to 150g/t at Isa-Hilton.

Has all the hallmarks of a sedex deposit with that high grading PB, ZN and AG - the Cu grades are fantastic as well and over some decent sized intercepts.