I read somewhere that I should only use one gram of SMB if I estimate that there is one gram of gold that is in the liquid. Of course, I will not substitute that formula for the Stannous Chloride testing. I would just like to know if it is a tried and true way to save on the amount of SMB used.
SMB and how much to use
- Thread starter Smitty
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Smitty,
You add SMB in small doses until the solution no longer tests positive for gold with Stannous Chloride.
The loss of yellow color of the solution is a good indication that you are getting close.
The smell of SO2 (sulfur dioxide) is another indicator.
In my opinion SMB is cheap and a little extra is better than too little.
If your solution contains a lot of dissolved copper (a dark green color) be careful not to over do it with the SMB as the excess will drop some cuprous chloride ( off white powder) with the gold. For this and other reasons, it is bad practice to drop gold with SMB from solutions full of copper and other base metals. As Harold consistently states:
Always remove as much of the base metals as possible before dissolving the gold into solution.
Steve
You add SMB in small doses until the solution no longer tests positive for gold with Stannous Chloride.
The loss of yellow color of the solution is a good indication that you are getting close.
The smell of SO2 (sulfur dioxide) is another indicator.
In my opinion SMB is cheap and a little extra is better than too little.
If your solution contains a lot of dissolved copper (a dark green color) be careful not to over do it with the SMB as the excess will drop some cuprous chloride ( off white powder) with the gold. For this and other reasons, it is bad practice to drop gold with SMB from solutions full of copper and other base metals. As Harold consistently states:
Always remove as much of the base metals as possible before dissolving the gold into solution.
Steve
