Prophet beard hair

حَدَّثَنَا مَالِكُ بْنُ إِسْمَاعِيلَ، حَدَّثَنَا إِسْرَائِيلُ، عَنْ عُثْمَانَ بْنِ عَبْدِ اللَّهِ بْنِ مَوْهَبٍ، قَالَ أَرْسَلَنِي أَهْلِي إِلَى أُمِّ سَلَمَةَ بِقَدَحٍ مِنْ مَاءٍ ـ وَقَبَضَ إِسْرَائِيلُ ثَلاَثَ أَصَابِعَ ـ مِنْ فِضَّةٍ فِيهِ شَعَرٌ مِنْ شَعَرِ النَّبِيِّ صلى الله عليه وسلم وَكَانَ إِذَا أَصَابَ الإِنْسَانَ عَيْنٌ أَوْ شَىْءٌ بَعَثَ إِلَيْهَا مِخْضَبَهُ، فَاطَّلَعْتُ فِي الْجُلْجُلِ فَرَأَيْتُ شَعَرَاتٍ حُمْرًا‏.‏

Narrated IsraiI: Uthman bin Abdullah bin Mauhab said, "My people sent me with a bowl of water to Um Salama." Isra'il approximated three fingers ('indicating the small size of the container in which there was some hair of the Prophet. `Uthman added, "If any person suffered from evil eye or some other disease, he would send a vessel (containing water) to Um Salama. I looked into the container (that held the hair of the Prophet) and saw a few red hairs in it,"

Sahih al-Bukhari 5896 https://sunnah.com/bukhari:5896