Mercury tetrathionate

Mercury fulminate dissolves readily in an aqueous solution of potassium cyanide to form a complex compound from which it is reprecipitated by the addition of strong acid. It dissolves in pyridine and precipitates again if the solution is poured into water. A sodium thiosulfate solution dissolves mercury fulminate with the formation of mercury tetrathionate and other inert compounds, and this reagent is used both for the destruction of fulminate and for its analysis.10 The first reaction appears to be as follows. 

Luther et al. (1991) employed square wave voltammetry for the determination of thiosulphate, sulphite and tetrathionate. They used an EG B Princeton Applied Research Model 383B-4 in conjunction with a Model 303 static dropping mercury electrode. 

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