What is the ruling on wearing watches that contain gold parts in their movement, whether unseen or visible, given that the watch itself is made of iron?

It is forbidden for men to wear gold, due to the Prophet's (peace and blessings be upon him) prohibition of it, except for a small amount that is secondary to something else, such as a gold bezel in a ring, or a small amount of gold in a wristwatch, especially if it is hidden like the internal mechanisms of the watch. This is a point of contention among jurists.