Sahih al-Bukhari 170
Narrated Ibn Seereen:
I said to `Abida, "I have some of the hair of the Prophet (ﷺ) which I got from Anas or from his family." 
`Abida replied. "No doubt if I had a single hair of that it would have been dearer to me than the whole 
world and whatever is in it."
حَدَّثَنَا مَالِكُ بْنُ إِسْمَاعِيلَ، قَالَ حَدَّثَنَا إِسْرَائِيلُ، عَنْ عَاصِمٍ، عَنِ ابْنِ سِيرِينَ، قَالَ قُلْتُ لِعَبِيدَةَ عِنْدَنَا مِنْ شَعَرِ النَّبِيِّ صلى الله عليه وسلم أَصَبْنَاهُ مِنْ قِبَلِ أَنَسٍ، أَوْ مِنْ قِبَلِ أَهْلِ أَنَسٍ فَقَالَ لأَنْ تَكُونَ عِنْدِي شَعَرَةٌ مِنْهُ أَحَبُّ إِلَىَّ مِنَ الدُّنْيَا وَمَا فِيهَا‏.‏