Potassium thiocarbonate as a precipitant for platinum metals

Potassium thiocarbonate reagent is proposed for the gravimetric determination of ruthenium(III), rhodium(III), palladium(II) and platinum(IV) in a highly acidic medium (pH 0.5-0.7) under suitable conditions. Ni, Zn, Mn(II), Al, Fe(III), Ti(IV), Zr, Th, Ca, Ba, Sr and Mg do not interfere. The largest relative error is 0.7% and the average error 0.2%.