Answer
selling carrion to a non-Muslim
✅Answer: Please refer to the following narrations:
1 عَنِ السَّكُونِيِّ عَنْ أَبِي عَبْدِ اللَّه قَالَ: السُّحْتُ ثَمَنُ الْمَيْتَةِ وَ ثَمَنُ الْكَلْبِ وَ ثَمَنُ الْخَمْرِ وَ مَهْرُ الْبَغِيِّ وَ الرِّشْوَةُ فِي الْحُكْمِ وَ أَجْرُ الْكَاهِنِ.
📚Al-Kafi vol. 5, p. 126
Imam al-Sadiq, blessings of God be upon him, said: Unlawful earning is the price of a carcass, the price of a dog, the price of wine, the dowry of adultery, a bribe in judgment, and the wage of a soothsayer!
2 عَنْ حَمَّادِ بْنِ عَمْرٍو وَ أَنَسِ بْنِ مُحَمَّدٍ عَنْ أَبِيهِ جَمِيعاً عَنْ جَعْفَرِ بْنِ مُحَمَّدٍ عَنْ آبَائِهِ فِي وَصِيَّةِ النَّبِيِّ لِعَلِيٍّ قَالَ: يَا عَلِيُّ مِنَ السُّحْتِ ثَمَنُ الْمَيْتَةِ وَ ثَمَنُ الْكَلْبِ وَ ثَمَنُ الْخَمْرِ وَ مَهْرُ الزَّانِيَةِ وَ الرِّشْوَةُ فِي الْحُكْمِ وَ أَجْرُ الْكَاهِنِ.
📚Al-Faqih vol. 4, p. 363
Imam al-Sadiq, blessings of God be upon him, said: The Messenger of God, peace be upon him and his family, said in his will to Ali, blessings of God be upon him: O Ali! Among the unlawful earnings are the price of a carcass, the price of a dog, the price of wine, the dowry of an adulterous woman, a bribe in judgment, and the wage of a soothsayer!
✅In the above narrations and others, the price of a carcass, such as a dead chicken or sheep, is absolutely considered among the unlawful earnings, and selling it to unbelievers is not an exception. Therefore, it is not permissible to sell a carcass to any type of unbeliever, such as Sabeans and others.
According to a narration in the book Bihar, the Sabeans are a group of unbelievers who have adopted the belief of denying the prophets and messengers of God and invalidating the divine laws, saying that whatever they have brought is false, and they have denied the divine oneness of God, the prophethood of the prophets, the apostleship of the messengers, and the succession of the successors.
✅However, there is a specific situation in which selling a carcass to a non-Muslim and unbeliever is permissible, as mentioned in the following hadiths:
3 عَنِ الْحَلَبِيِّ قَالَ سَمِعْتُ أَبَا عَبْدِ اللَّه يَقُولُ إِذَا اخْتَلَطَ الذَّكِيُّ وَ الْمَيْتَةُ بَاعَهُ مِمَّنْ يَسْتَحِلُّ الْمَيْتَةَ وَ یَأَكُلَ ثَمَنَهُ.
📚Al-Kafi vol. 6, p. 260
Halabi said: I heard Imam al-Sadiq, blessings of God be upon him, say: When an animal that has been ritually slaughtered gets mixed with a carcass, one can sell (all of it together) to someone who considers a carcass lawful (i.e., to a non-Muslim) and eat its price!
4 عَنِ الْحَلَبِيِّ عَنْ أَبِي عَبْدِ اللَّهِ أَنَّهُ سُئِلَ عَنْ رَجُلٍ كَانَ لَهُ غَنَمٌ وَ بَقَرٌ وَ كَانَ يُدْرِكُ الذَّكِيَّ مِنْهَا فَيَعْزِلُهُ وَ يَعْزِلُ الْمَيْتَةَ ثُمَّ إِنَّ الْمَيْتَةَ وَ الذَّكِيَّ اخْتَلَطَا كَيْفَ يَصْنَعُ بِهِ قَالَ يَبِيعُهُ مِمَّنْ يَسْتَحِلُّ الْمَيْتَةَ وَ يَأْكُلُ ثَمَنَهُ فَإِنَّهُ لَا بَأْسَ.
📚Al-Kafi vol. 6, p. 260
Imam al-Sadiq, blessings of God be upon him, was asked about a person who has a flock of sheep and cows and separates those that have been ritually slaughtered and also separates the carcasses, but they later get mixed together. What should he do? The Imam said: He should sell it to someone who considers a carcass lawful (i.e., to a non-Muslim) and eat its price, and there is no harm in that!
✅According to the two above narrations and others, if ritually slaughtered animals get mixed with carcasses and cannot be distinguished, one can sell the whole lot to someone who considers eating a carcass lawful and use its price, but it is not permissible to sell it to a Muslim.
✅In the hadith from 📚Al-Tahdhib vol. 1, p. 279, it is also mentioned that it is permissible to sell dough that has been dripped with wine, nabidh, or blood to Jews and Christians, because such dough is not usable for a Muslim, but it is necessary to note that this case, and the specific case of selling ritually slaughtered animals mixed with carcasses to non-Muslims, are specific situations and cases from which a general conclusion cannot be drawn.