(45g dried MgSO4, 55g Glycerol, 500mg Phenol)
Found it here - http://www.mombu.com/medicine/laboratory/t-magnesium-sulfate-paste-1953030.html
Simply mix your epsom salts with a small amount of water - a little at first -- and stir until it becomes a paste. You can apply it directly, or as part of a poultice.
Apply paste to piece of gauze or lint. Place on skin and bandage. Change after 12-24 hours.
No, Mg is not a reductant for sulfate.
No it will not, because sulfate is not an oxidant to Mg.
sodium and potassium