A common kohl-pot in the shape of a Martini Henry cartridge / bullet. Connected to it with a silver chain is the application stick.
Omani men are not supposed to wear jewelry, however they are allowed to wear weapons, hence weapons were adorned to become a form of jewelry!
Both men and women in Oman wear the cosmetic Kohl round the eye, Which gives the eyes more expression. Local believe is that it improves eyesight however in practice many people LOST eyesight due to eye infections by the practice of passing the application stick around from person to person.