Exhaust Front Pipe

[Daviewonder 533 3 Cars]

Hello

 

My standard front pipe rusted through on my 1.9 recently which was part of the 2 piece system with olive fittings, I had a spare 3 piece sleeve fitting exhaust in the garage at home that I then fitted, on fitting it I noticed that the front pipe was made of aluminium, is this normal for 3 piece system front pipes or is it some strange oddity?

[welshpug 1,666]

was it not aluminiumised steel rather than straight aluminium?

[Daviewonder 533 3 Cars]

Im not sure, I thought it was aluminium as it had oxidization on it and it weighed hardly anything.