Chain with a Ring
Question :

Can a man wear a chain with a ring (not gold) on his neck?

Answer :

Wearing the ring in a chain around one’s neck by itself is permissible, unless doing so is considered to be imitation of women or it leads to humiliation or similar results which are prohibited to bring about, in which cases it becomes impermissible.

Peircings
Question :

Are Muslim men allowed to get their ears or any parts of their body pierced?

Answer :

It is not permissible for men to imitate women. Piercing is permissible if it does not lead to that nor to any other prohibitions.

Earrings for Men
Question :

Is wearing earrings permissible for men?

Answer :

It is prohibited for men to wear earrings if it is to imitate women with the intention of femininity.