Running out of one refined metal switches to steel as a buildin material

- Build something from a refined metal, e.g. iron. Build so much of it that you run out of this material.

- The game will switch to steel as building material, even if other refined metals are available.

- To make it even worse, it switches the material for all buildings, not just the one being built.

This means that one can build from the precious steel even when not intended. This has happened to me several times and it's very annoying. The game should switch to other refined metals before switching to steel.