715 – Fadala ibn ʿUbayd (may Allah be pleased with him) reported: “On the day of Khaybar I purchased a necklace for twelve dinars. It contained gold and beads. When I took it apart, I discovered that the gold in it alone was worth more than twelve dinars. I related this to the Prophet ﷺ, and he said, ‘It must not be sold until it has been separated.’ ” Muslim narrated it (1).

Glossary of terms
• qilādah: an ornament worn around the neck.
• dinar: a gold coin that weighs one mithqāl; on modern scales a mithqāl is about 4.25 grams, a figure frequently cited by scholars.
• kharaz: perforated beads made from various materials and strung together for adornment.
• fa-faṣaltuhā: i.e., I broke up the necklace and distinguished its beads from its gold.

Points derived from the hadith

1. It is impermissible to sell gold for gold except on an equal-for-equal basis. ʿUbāda ibn al-Ṣāmit’s hadith explicitly prohibits trading gold for gold unless it is like for like; whoever gives or takes an excess has committed usury.
2. The Prophet ﷺ forbade selling a necklace that contains gold whose amount is unknown for an equivalent sum of gold, because equality between the stated twelve dinars and the undetermined quantity of gold inside the necklace is uncertain. Ignorance of whether the two amounts are equal carries the same ruling as certainty that they are unequal: both render the transaction unlawful.