It is impermissible to sell gold jewelry for men to wear
13-11-2013 | IslamWeb
Question:
Can is sell gold rings and jewellery which is wore by men.
Answer:
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad 
is His slave and Messenger.
We have previously clarified in Fatwa 89085 that it is forbidden for men to wear gold and that gold is specifically for women. So, if the gold jewelry that you want to sell is made for men and is sold for them to wear, then it is forbidden for you to sell it as this is helping them in sin and wrongdoing. Allaah says (what means): {…but do not cooperate in sin and aggression.} [Quran 5:2]
Selling gold jewelry for men to wear is like selling juice for someone who turns it into alcohol [wine or any kind of intoxicants]. It was reported that a person in charge of the farm of Sa’d ibn Abi Waqqaas 
told him about a crop of grapes that is not good to make raisins and that it is only good to sell for someone who will squeeze it (into wine). So, Sa’d ordered that these grape be uprooted and said: “What a wretched old man I would be if I were to sell wine.”
Moreover, the Fatwa of the Permanent Committee (for issuing Fataawa) reads: “If anything is used in a forbidden manner or one thinks that it will most likely be used in a forbidden manner, then it is forbidden to manufacture it, import it, or sell it, or promote it among the Muslims.”
Allaah Knows best.