I don't believe that development costs should be entailed amongst the CAPEX and production costs however lets say that we stick to your figures for argument sake.
Current gold price = US$1334/oz
If we go on a steady state of production at 100,000 oz/yr as an example:-
$1334 - $914 = $420 profit margin/oz
$420 x 100,000 = 42,000,000 x 75% = $31,500,000 once BEE takes it's stake although for the first year or 2 GDO should keep all funds for the BEE's portion of the CAPEX that was outlaid by GDO initially.
Take your pick:-
$31,500,000 x 12 = $378,000,000 MCAP
or
$42,000,000 x 12 = $504,000,000 MCAP
(Current market cap at around 234 million) I am being conservative here and I am not taking into account that GDO is forecast to produce 120,000 oz/au this year.
GDO Price at posting:
29.0¢ Sentiment: LT Buy Disclosure: Held