an alloy suitable for the galvanization of steels by an immersion galvanization process , including gavanization of steels containing silicon , which alloy comprises zinc of commercial purity and has a lead content of the order of 1000 to 20000 p . p . m . by weight , an aluminium content of from 100 to 5000 p . p . m . by weight , a magnesium content of from 10 to 1000 p . p . m . by weight and a tin content of from 300 to 20000 p . p . m . by weight . a galvanization process using the said alloy is also described .