Here are some comments I made previously on the Zn at Southern...

Here are some comments I made previously on the Zn at Southern Nights/Wagga Tank that might help.

https://hotcopper.com.au/threads/an...hts-drilling.3824076/page-51?post_id=28775609

https://hotcopper.com.au/threads/an...3824076/page-49?post_id=28770707#.W0WYwIo_WhA

I don’t really have much to add at this stage.

As far as SFR goes the bornite zone at Monty, which is in the primary ore has been touted as a potential area of DSO mining in company presentations. Grades in drill intersections there are as high as 36% Cu and they have broad widths in drill intersections as wide as 25.8m at 24.1% Cu. Silly idiots for selling this to SFR.

http://clients2.weblink.com.au/news/pdf_2\01704281.pdf

Below also attached is an SFR presenatation from Nov 2011 showing the supergene chalcocite zone at DeGrussa which at the time had an indicated resource of 250,000t at 17.6%Cu and 2.6g/t gold. The DSO resource from this zone at the time (I don’t know how much was eventually mined and shipped) was 140,000t at 25.6% Cu and 2.5g/t gold.

http://www.sandfire.com.au/images/files/28Nov11-2011AnnualGeneralMeetingPresentation.pdf

So as a general answer based on those examples circa 25% Cu seems to work but it would depend on a number of other factors in relation to the overall mine plan for the main deposit. Esh