Sahl reported,

He was asked about the wound the Prophet ﷺ suffered on the Day of Uhud.He said, "The Prophet's ﷺ face was wounded, his front tooth was broken, and the helmet was crushed upon his head. Fatimah, peace be upon her, was washing away the blood while Ali held the water. When she saw that the bleeding only grew heavier, she took a piece of straw mat and burned it until it turned to ash, then pressed it onto the wound, and the bleeding stopped."

Bukhari 2911

Sahih

حدثنا عبد الله بن مسلمة حدثنا عبد العزيز بن أبي حازم عن أبيه

عن سهل رضي الله عنه

أنه سئل عن جرح النبي ﷺ يوم أحد فقال جرح وجه النبي ﷺ وكسرت رباعيته وهشمت البيضة على رأسه فكانت فاطمة عليها السلام تغسل الدم وعلي يمسك فلما رأت أن الدم لا يزيد إلا كثرة أخذت حصيرا فأحرقته حتى صار رمادا ثم ألزقته فاستمسك الدم

البخاري 2911صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Bukhari
Book
Jihad and expeditions
Chapter
Wearing the helmet
Numbering
Darussalam 2911
Bukhari 2911