Gold and silver

In all their dealings and transactions Muslims should be mindful of Allah and pay heed to His commands. We should never violate the teachings of Shari`ah under any circumstances. As far as Islam is concerned, it is not permissible to exchange old gold for new even if the difference in value is paid to the

Aslamu Alekum Dear Brother, I really wanna know about gold being Haram in Islam for men wearing it, a friend of mine doesnt believe this. He says he needs to see a Verse of Holy Quran or a Hadees to believe he claims he read so many books of Hadees and it never mentions any thing about this. How can I get him to believe or is there a Hadees? Besides saying Iqama should be done even individually too or only in Gathering?With Regards