OBM What is Fair Value ?

Hi all, just watching the slide on OBM over the last 2 weeks. & not just OBM a lot of Goldies have slid, & today lotsa down... eg BC8
My gut feel fair value for OBM was around $1- 1.10.
Just wondering has anyone tried to value OBM?

I do not use NPV, I tend to use after tax cash flows & like to work out it out for Reserve and Resource.
For OBM Rsv is small - reminds me of Medusa Mining years ago where they just did enough drilling to find the next years gold. In that case I use a RSV of 2/3rds of RSC

So I ran some scenarios - looking at 10 years production
worst case was $A4600 POG and $2750 AISC, 2.6 g/t & Mill at 1.4Mtpa . with a A$157m Taz credit .
This is 121kOz per year - so 10 years is so 1.2MOz mined which is around 2/3rds of RSC.
The result - we end up with todays closing share price of 93c. at $4100 SP is 70c

So no new gold no higher grade & either $A go up 10% or gold drops 10% plus. With $A link to iron ore and china economic slow down, I cant see our $A rising or with debt , wars etc I cannot see Gold dropping. If Gold drops I reckon $A will drop so we will retain around $A5000.

If we run at current processing 1.4Mtpa - 3.2g/t - we get 150kOz per year - AISC $2500, looking at $1.55 - 10 years

Looking at the last quarterly Riverina was pushing 5g/t then dropping back to 4.4 g/t . So what about 4.4 g/t - you get 200kOz / yr & $2.10....

Other scenarios attached
ATCF = After Tax Cash Flow $Am / year
SP->10EPS = (157 + 10 xATCF) / SOI, share price on 10 years EPS

Anyway pretty basic - as takes cash for exploration & starting underground mines so if we take the $157m Tax credit and assume this is used for CAPEX / EXP it drops the SP by 9c... eg upper right would be 1.19 not 1.28

Thoughts....