Professor I suspect that you think you know more than you do about the refining and recovery of precious metals and snapping at other members of the forum will gain you no friends but a possible ban from the forum.
You are quite wrong when you say gold will not dissolve in the presence of base metals, it will readily dissolve but will then cement back out as the acid consumes the base metals until all base metals are consumed then you will have the gold go into solution, if as you say you are using chemistry to determine what you have then making stannous is surely easy, it's a lot easier than dissolving whatever it is you have, and will tell you whether you have any gold there or not.
I suspect that what you have is nothing more than gold bearing ore which has arsenic mixed in with all the other elements and if that is the case I am not suprised you have had some very nasty experiences trying to either melt or dissolve it, it is the toxic element that gave cobalt its reputation back in the 1700s.
My advice is to leave it well alone or get a proper assay done before you kill yourself and possibly your family and neighbours, you cannot by pure chemistry alone determine what you have especially without the right chemicals or equipment.
To be blunt most gold ore runs at around 1/2 to 5 ounces a ton, most at the lower number, that means if you have 100 kilos you may have between 1.5-15 grams of gold and your risking your health and life to try and recover that, I suspect someone is not telling you the truth as to its origin but simply using you to try to discover whether there is gold there or not without paying for a decent assay.
Even if you do recover the gold is it worth the cost to your health, will you want to expose yourself to the arsenic fumes continuously until it kills you!
You are quite wrong when you say gold will not dissolve in the presence of base metals, it will readily dissolve but will then cement back out as the acid consumes the base metals until all base metals are consumed then you will have the gold go into solution, if as you say you are using chemistry to determine what you have then making stannous is surely easy, it's a lot easier than dissolving whatever it is you have, and will tell you whether you have any gold there or not.
I suspect that what you have is nothing more than gold bearing ore which has arsenic mixed in with all the other elements and if that is the case I am not suprised you have had some very nasty experiences trying to either melt or dissolve it, it is the toxic element that gave cobalt its reputation back in the 1700s.
My advice is to leave it well alone or get a proper assay done before you kill yourself and possibly your family and neighbours, you cannot by pure chemistry alone determine what you have especially without the right chemicals or equipment.
To be blunt most gold ore runs at around 1/2 to 5 ounces a ton, most at the lower number, that means if you have 100 kilos you may have between 1.5-15 grams of gold and your risking your health and life to try and recover that, I suspect someone is not telling you the truth as to its origin but simply using you to try to discover whether there is gold there or not without paying for a decent assay.
Even if you do recover the gold is it worth the cost to your health, will you want to expose yourself to the arsenic fumes continuously until it kills you!