It definitely looks as if the surface has been treated in some way - the effect is nice and it must be deliberate.
I haven't ever handled corroso myself, but I'll never forget the time here, many years ago, when a lovely chap (who isn't here any more) found a Seguso corroso hippopotamus and posted it here.
I think he eventually sold it for about £4,000! You don't forget that sort of excitement. He wasn't expecting it to ba anything particularly important.
So I'm afraid I really was just using "fancy words".

I have a small beige posy vase, which has an illegible signature/mark and a rough but smooth surface, with patches of iridesence inbetween lumpy bits, which also might be corroso, but it doesn't look like yours and isn't nearly such an interesting or well designed thing.
I'd wondered if it would pour liquid myself, Anne!