Sulfide ore test for gold using stannous chloride,
A couple of methods come to my mind,
Take a sample and incinerate red hot to burn off sulfur dioxide gas (SO2 gas) and any sulfur, roasting the ore to oxides, then a boiling washes in HCl, and rinse’s till clear, then add this sample to aqua regia, evaporate off nitric acid and test with stannous chloride,
Another,
A simple test in the field for gold in sulfide ore:
Any gold sulfide ore may be dissolved by fusion with a pinch of powdered mineral, in a surplus mix of one part ammonium chloride and 2.5 parts of ammonium nitrate,
The melted fusion is cooled, then dissolved in a few drops of HCl hydrochloric acid, putting a drop of this solution on filter paper, and a drop of stannous chloride added, a red to violet color indicates presence of gold
This will not tell you how much is present, but can be an indicator of the presence of gold.
A quick search of this method on Google:
http://www.google.com/search?hl=en&source=hp&q=test+of+sulfide+ore+fusion+ammonium+nitrate+and+ammonium+chloride+stannous+chloride&gbv=2&oq=test+of+sulfide+ore+fusion+ammonium+nitrate+and+ammonium+chloride+stannous+chloride&aq=f&aqi=&aql=&gs_l=hp.3...2125.37423.0.39360.89.13.3.73.75.0.203.1534.4j8j1.13.0...0.0.8ww0XsO2344
Do not forget the tried and true method of assaying the ore.
