What happens when you heat an iron rod on a flame?

What happens when you heat an iron rod on a flame ? Do you find any change in colour while heating an iron rod ?

When we heat an iron rod, some amount of heat energy that was absorbed by iron rod is emitted as light. First iron turns into red (lower energy corresponding to higher wavelength) and as the temperature rises it glows and turns into orange, yellow, blue respectively (higher energy and lower wavelength). If we go on heating the rod it turns into white light which includes all visible wavelengths.