Your wrought item is made out of mild steel (and not "Wrought Iron") and to prevent your item from rusting it has been coated in a mixture of linseed oil and turps or beeswax. This will provide a protective but not permanent coating (especially if exposed to the weather). The reason behind doing this and not just painting it, is that the natural coating will still let the steel underneath oxidize creating that lovely deep rich black patina that comes with aged wrought iron.
Rust is the oxidization of the iron atoms (FE) in the steel to form iron oxide and will mainly appear around welds, joins and wear areas, and will spread from there. That's why, especially in cars, rust is referred to as cancer.
If you notice any rusting on your item do not despair, rust only affects the very surface of the steel to start with. If left, it will penetrate deeper into joins and welds where it cannot be reached without major effort.
To deal with the affected area: if it is just a little spot, then scrub with a wire brush or some steel wool. If it is a major area that is affected, especially a join or weld, make up a 1:5 parts bi-carb to water solution (make sure the bi-carb is dissolved). Then scrub with a tooth brush and vinegar, making sure that you get plenty of vinegar into the nooks and crannies. Do this outside in the sun and leave it for 5 mins, the sun will warm the acid in the vinegar and that will dissolve the iron oxide. Now is the time to use the bi-carb solution; be very liberal with it, this will neutralize the acid, then rinse with clean water. Dry everything off and leave for 30 mins in the sun to make sure it has dried off completely, go as far as using a hair dryer or heat gun on the joins. Make a 1:2 parts mixture of linseed oil and turps and paint this on and around the area; don't worry if the area is hot, this will just help with the coating. Make sure to concentrate on joins and welds. Leave this for another 30-60 mins then wipe off the excess with a non-fluffy rag. You will be able to move your item inside if that is where it was but remember it will still be sticky for a few days.
That should take care of your rust problem.