UPDATE 1-Brazil's Metalúrgica Gerdau considers potential offering

SAO PAULO, Oct 1 (Reuters) - Matalúrgica Gerdau SA, which controls Brazilian steelmaking group Gerdau SA, said on Thursday that consideration of a potential share offering is preliminary and has yet to be decided, responding to a newspaper report saying the plan could help fetch 1.5 billion reais ($380 million) from investors.