✅ Answer: Due to the existence of the following two narrations, it is advisable to avoid consuming powdered sheep horn or the horns of other animals:

قَالَ أَبَانٌ ثُمَّ قَالَ أَبُو عَبْدِ اللَّهِ یُکْرَهُ مِنَ الذَّبِیحَةِ عَشَرَةُ أَشْیَاءَ مِنْهَا الطِّحَالُ وَ الْأُنْثَیَانِ وَ النُّخَاعُ وَ الدَّمُ وَ الْجِلْدُ وَ الْعَظْمُ وَ الْقَرْنُ وَ الظِّلْفُ وَ الْغُدَدُ وَ الْمَذَاکِیرُ

📚 'Ilal al-Shara'i, Vol. 2, p. 562

In a hadith, Aban bin Uthman narrates: Then Imam Sadiq (peace be upon him) said: 'There are ten disliked things from a slaughtered animal, among them are the spleen, testicles, spinal cord, blood, skin, bones, horns, hooves, glands, and the male organ.'

عَنِ السَّیَّارِیِّ عَنْ مُحَمَّدِ بْنِ جُمْهُورٍ عَمَّنْ ذَکَرَهُ عَنْ أَبِی عَبْدِ اللَّهِ قَالَ حُرِّمَ مِنَ الذَّبِیحَةِ عَشَرَةُ أَشْیَاءَ وَ أُحِلَّ مِنَ الْمَیْتَةِ (عَشَرَةُ أَشْیَاءَ) فَأَمَّا الَّذِی یَحْرُمُ مِنَ الذَّبِیحَةِ فَالدم وَ الْفَرْثُ وَ الْغُدَدُ وَ الطِّحَالُ وَ الْقَضِیبُ وَ الْأُنْثَیَانِ وَ الرَّحِمُ وَ الظِّلْفُ وَ الْقَرْنُ وَ الشَّعْرُ

📚 Mahasin, Vol. 2, p. 471

Imam Sadiq (peace be upon him) said in a hadith: 'Ten things from a slaughtered animal are forbidden... So what is forbidden from a slaughtered animal is blood, dung, glands, spleen, male organ, testicles, uterus, hooves, horns, and hair...'

✅ Note: No specific contradiction to these two narrations has been observed.

اللَّهُمَّ فَصَلِّ عَلَی مُحَمَّدٍ وَ آلِ مُحَمَّدٍ وَ عَجِّلْ لِوَلِیِّکَ الْفَرَجَ وَ الْعَافِیَةَ وَ النَّصْرَ