re: tastarga The industry term for gold recovery in this instance is 'refining'- not 'smelting'. If the latter, you are implying it is refractory which it is not.
We have discussed this issue in detail earlier this year.
Go away and read the "Cost Estimation Handbook" Monograph 20, as published by the Australian Institute of Mining and Metallurgy (yes I am a member of the Institute).
Cheers,TAS
