Rusting of...or The rust of....

[Tamdang]

I happened to see a sentence in "Error identification" like this.
-The rust of ......
But I think it should be The rusting of.......
Please help me explain it clearer. What is the difference between RUST and RUSTING?
Thanks.

[Alan]

It would depend on what kind of noun followed the word 'of' (which you fail to mention), but if it were the name of some object, then 'rusting' would almost certainly be the correct choice.