SHAFAQNA – The Grand Ayatollah Vahid Khorasani answered questions about men wearing gold.
Question: Is there a problem for men wearing white gold for example as engagement ring? And if it is Haram, the Salaats which has been performed wearing it, are void (Batel) or just the action (of wearing it) is Haram?
The Grand Ayatollah Vahid: Wearing gold ring and things like that, is Haram for men, and performing Salaat with them is void (Batel), and there is no difference between white or yellow gold; and if it is not gold, for example platinum, there is no problem. And if a man performs Salaat, and does not know or forgets that his ring or cloths are made of gold, or in doubt, his Salaat is correct. These rulings are applied for wearing anything that by common law is called gold, whether it is white or yellow.
Source: PERSIAN SHAFAQNA