Refining Silver Alloy : Ag-35% / Cu-37% / Sn-2.5% / Zn-rest

[xxrayexx]

Hi, I hope someone can help me with ideas on safely refining a silver alloy containing below composition:
Ag-35% / Cu-37% / Sn-2.5% / Zn-rest. I have large volume of the material - (20Kg) and would pretty much want to avoid the use of Nitric acid or any other acid for reasons that it is not permitted in my area.

 

[Lino1406]

No acid, no refining

 

[kurtak]

No acid, no refining

in other words - without acid you can't refine it - that leaves you with ONE option - sell it to a refiner

Kurt