Cobalt siccative is the best siccative we can produce for artistic painting, and is highly concentrated because it contains 1,5% of cobalt. For faster drying, this siccative is added at the quantity of 5 ml per 1 liter of pure linseed oil. Thus, contents of the bottle (100 ml) suffices for 20 litres of linseed oil. When used ordinarily it is added by drops. A greater addition makes no benefit, however harms in such a way that the upper coat dries very fast, and hence forms a solid film and the paint dries into depth with diffulties.