alkafi-8844Vol. 5, p. 192-193
الذَّهَبُ بِالذَّهَبِ وَ الْفِضَّةُ بِالْفِضَّةِ وَزْناً بِوَزْنٍ سَوَاءً لَيْسَ لِبَعْضِهِ فَضْلٌ عَلَى بَعْضٍ وَ تُبَاعُ الْفِضَّةُ بِالذَّهَبِ وَ الذَّهَبُ بِالْفِضَّةِ كَيْفَ شِئْتَ يَداً بِيَدٍ وَ لَا بَأْسَ بِذَلِكَ وَ لَا تَحِلُّ النَّسِيئَةُ وَ الذَّهَبُ وَ الْفِضَّةُ يُبَاعَانِ بِمَا سِوَاهُمَا مِنْ وَزْنٍ أَوْ كَيْلٍ أَوْ عَدَدٍ أَوْ غَيْرِ ذَلِكَ يَداً بِيَدٍ وَ نَسِيئَةً جَمِيعاً لَا بَأْسَ بِذَلِكَ وَ مَ
Exchange of gold for gold, silver for silver by weight in equal quantities is balanced. One does not have preference over the other. Silver can be exchanged for gold and gold can be exchanged for silver as you like in a hand in hand transaction and it is not harmful but it is not lawful on credit. Gold and silver can b