Hi Grivarta- No probs let me fill you in.
As a general rule of thumb for underground mining of the Bushveld deposits. Anything above 1.8g/t 3PGE+Au and > 1m thickness is considered economically mineable.
If less than 1m which SPDs UG2 is, then accumulation value should not be less than 180 cm*g/t SPDs UG2 is 71cm x 7.1g/t = 546cmxg/t so is well above economic.
Look at the Financials for Modikwa and Two Rivers (African Rainbow Minerals) - they straddle the Bengwenyama Project North and South- Essentially mining the same ore body.
Modikwa is only doing UG2 at present at an average width of
61cm (see figure below). Two Rivers produces from UG2 and Merensky.
Cash Cost for Modikwa ~ USD 114/ton at ZAR:USD of 15.28. Cash cost for 6E ~ USD935 per ounce. Head grade is 4.51g/t on Modikwa UG2 (that accounts for dilution)
Cash Cost for Two Rivers ~ USD 59.2 per tonne, USD647 per ounce 6E. Head Grade 3.43g/t 6E
Using basket price of 3E+Au of USD3078 for UG2 at Modikwa of 4.51g/t = USD446 per ton dirt. or 7.5g/t Au equivalent at Au/oz of USD1850
Gotta also apply other factors recoveries, mining loss (pillars, declines etc), call factors and Modikwa comes in at a recovered value of about USD300/ton with chrome coming on stream about USD320 per ton.
Credits beyond pt,pd,rh,au are ru, ir, (6E) ni, cu adds about 14% to the ore value of 3E +Au. Modikwa are currently installing a Chrome concentrator on the tails which should add about 5-6% on the value of vanilla 3E+au.
S
o on any calc on value by SPD add ~20% to $/ton value as they only state 3E+Au.So SPD UG2 @ 7.7g/t 3PGE+Au with 36% dilution gives 4.93g/t 3PGE+Au head grade. At todays prices that's USD487 per ton add 20% for the 6E +ni+cu+cr credits of 20% and that is a value of USD585 per ton Pretty pretty goood.
Merensky is also economically viable at the grades SPD have as shown by two rivers mine head grade.
(20min delay)