Q 12:72

So when he furnished them forth with their provisions, he put the bowl in his brother's bag. Then a crier cried: "O you (in) the caravan! Surely, you are thieves! (70)They, turning towards them, said: "What is it that you have lost? (71)They said: "We have lost the bowl of the king and for him who produces it is (the reward of) a camel load; and I will be bound by it. (72) Yusuf had His Golden Bowl placed in Binyamin's Bag; a Plot to keep Him in Egypt After Yusuf supplied them with their provisions, he ordered some of his servants to place his silver bowl (in Binyamin's bag), according to the majority of scholars. Some scholars said that the king's bowl was made from gold. Ibn Zayd added that the king used it to drink from, and later, measured food grains with it since food became scarce in that time, according to Ibn 'Abbas, Mujahid, Qatadah, Ad-Dahhak and 'Abdur-Rahman bin Zayd. Shu'bah said that Abu Bishr narrated that Sa'id bin Jubayr said that Ibn 'Abbas said that the king's bowl was made from silver and he used it to drink with. Yusuf had the bowl placed in Binyamin's bag while they were unaware, and then had someone herald, أَيَّتُهَا الْعِيرُ إِنَّكُمْ لَسَارِقُونَ (O you (in) the caravan! Surely, you are thieves!) They looked at the man who was heralding this statement and asked him, مَّاذَا تَفْقِدُونَ - قَالُوا نَفْقِدُ صُوَاعَ الْمَلِكِ ("What is it that you have lost?" They said: "We have lost the bowl of the king..."), which he used to measure food grains, وَلِمَن جَاءَ بِهِ حِمْلُ بَعِيرٍ (and for him who produces it is a camel load), as a reward, وَأَنَا بِهِ زَعِيمٌ (and I will be bound by it.), as assurance of delivery of the reward.