To day it is very fashionable to use rusted cabinet hardware & door hardware in homes. Especially homes that have a Spanish or Mediterranean theme. Cast iron & steel can both be rusted as the metals have the same properties in their mixture. Left unsealed they will rust or oxidize naturally. The metal turns into red rust becomes flakey or powdery and comes off when you touch it. However there are several ways to seal it successfully. The European hardware companies are very good at it as they have a big market for traditional style country hardware from the 16th century on. There is a thriving restoration business for Antique iron hardware. So reproduction pieces must look authentic.
We have a range of hand made cast iron hardware. It is our own line. Frequently our customers request for it to be rusted. We do have several options available from a French Rust through to a very dark almost black rust. In the middle are the brown rusts. We have been able over the years to perfect the process and our customers love the look. Particularly people who are remodeling Spanish homes. The great asset is that over time the finish becomes better and unlike Brass Antiquing does not come off.
In finishing the metal properly it needs to be really clean to start. No oil or other sediment on it. Then it has to be completely rusted & left to so that the rust penetrates the iron deeply. After that comes the coloring, finishing and sealing. Traditionally wax is used for the sealing. It has to be done properly otherwise the rust will bleed through . The finish is great for home interiors. Cabinetry , doors and furniture. It is not guaranteed for exteriors applications. Done correctly it will enhance the look of all your cabinetry.