Non-metallic inclusions that arise because of different reactions during metal production are called natural or indigenous.
nˈɑːnmətˈælɪk ɪŋklˈuːʒənz ðæt ɚɹˈaɪz bɪkˈʌz ʌv dˈɪfɹənt ɹɪˈækʃənz dˈʊɹɹɪŋ mˈɛɾəl pɹədˈʌkʃən ɑːɹ kˈɔːld nˈætʃɚɹəl ɔːɹ ɪndˈɪdʒənəs.