Sayyiduna Fadalah bin Ubayd (may Allah be pleased with him) said: Necklaces containing beads and gold were brought to the Prophet (peace and blessings be upon him) while he was at Khaybar; this was spoils of war being sold. The Messenger of Allah (peace and blessings be upon him) gave the order concerning the gold that was in the necklace that it be removed. Then he (peace and blessings be upon him) said: "Sell gold for gold equal in weight."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 10550
Hanash (may Allah have mercy on him) said: We were with Sayyiduna Fadalah bin Ubayd (may Allah be pleased with him) on a military campaign. Hanash (may Allah have mercy on him) said: There came to me and my companions necklaces containing gold, silver and gems. I wanted to buy them, so I asked Sayyiduna Fadalah bin Ubayd (may Allah be pleased with him) about it, and Fadalah (may Allah be pleased with him) said: Remove its gold and put it in one pan of the scale, and put your gold in the other pan, then take only equal for equal, for I heard the Messenger of Allah (peace and blessings be upon him) say: "Whoever believes in Allah and the Last Day should take them only equal for equal."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 10551
Sayyiduna Fadalah bin Ubayd (may Allah be pleased with him) said: In the year of Khaybar, a necklace was brought to the Messenger of Allah (peace and blessings be upon him) in which beads were set with gold. A man had bought that necklace for seven or nine dinars. The Prophet (peace and blessings be upon him) said: "No, not until the two are separated." He said: I only intended the stones. He (peace and blessings be upon him) said: "No, not until the two are separated." The narrator said: So he returned it until they were separated.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 10552
Sayyiduna Fadalah bin Ubayd (may Allah be pleased with him) said: On the day of Khaybar I bought a necklace for twelve dinars. It contained some gold and some beads and gems. On separating them, I got more than twelve dinars' worth of gold. I mentioned this to the Prophet (peace and blessings be upon him), and he (peace and blessings be upon him) said: "It should not be sold until it has been separated."
(b) In the narration of Abu Dawud: the necklace was for twelve dinars, and it contained gold and beads.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 10553
Sayyiduna Fadalah bin Ubayd (may Allah be pleased with him) said: We were with the Messenger of Allah (peace and blessings be upon him) on the day of Khaybar, buying from the Jews an uqiyah of gold for two or three dinars. He (peace and blessings be upon him) said: "Sell gold for gold only equal in weight."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 10554