pleassssse help!!!! bioleching of gold with thiobacillus ferrooxidans

[ren]

I have been reading about this incredible process for months. And
still searching for a method to use it on gold bearing waste. What i
came to know is that they use T. ferrooxidans and Atomic Adsorption
Spectrometry. but my question is, how do u calculate the percentage of
gold in this process. I hope to hear from u guys... thank u very much