-demorol,
Any SOLUBLE mercury salt will do, quoting osmium and possibly labtop. Sulfate salts are insoluble. Nitrate, Halide, and others will definitely work. COnsult a general chemistry textbook, merck, etc. for sulubility guidelines of salts in aqueous solutions.
Soluble dosen't mean very soluble, either. As long as some dissolves, amalgamation goes, equilibrium shifts, amalgamation goes, yada yada yada. Transition metal salts are not very soluble. You're supposed to have at least a minimal amount of water in the al/hg depending on what variation you use. I know alcohol is present, factoring in, along with all of the other shit. Plainly, water is there. so is the water soluble mercury salt. It works.
Hope my tone isn't dry or antagonistic. I wasn't trying to be an asshole about it, just plain and simple. Good luck with any work that swid might be out to do