An-Najasat (impure and filthy things) which fall in cooking butter (ghee - which is obtained by evaporating moisture from butter) and water Sahih al-Bukhari 237

Arabic hadith text
حَدَّثَنَا أَحْمَدُ بْنُ مُحَمَّدٍ، قَالَ أَخْبَرَنَا عَبْدُ اللَّهِ، قَالَ أَخْبَرَنَا مَعْمَرٌ، عَنْ هَمَّامِ بْنِ مُنَبِّهٍ، عَنْ أَبِي هُرَيْرَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏"‏كُلُّ كَلْمٍ يُكْلَمُهُ الْمُسْلِمُ فِي سَبِيلِ اللَّهِ يَكُونُ يَوْمَ الْقِيَامَةِ كَهَيْئَتِهَا إِذْ طُعِنَتْ، تَفَجَّرُ دَمًا، اللَّوْنُ لَوْنُ الدَّمِ، وَالْعَرْفُ عَرْفُ الْمِسْكِ ‏"
Translation
Narrated Abu Huraira

The Prophet (ﷺ) said, "A wound which a Muslim receives in Allah's cause will appear on the Day of Resurrection as it was at the time of infliction; blood will be flowing from the wound and its color will be that of the blood but will smell like musk."