ˈeɪ "mˈoʊst fˈeɪθfəl" ˈɪndᵻkˌeɪɾɚ plˈænt ɪz ˈɑːsɪməm sɛntɹˈeɪlɪˌæfɹɪkˌænəm, ðə "kˈɑːpɚ plˈænt" ɔːɹ "kˈɑːpɚ flˈaʊɚ" fˈɔːɹmɚli nˈoʊn æz bᵻsˈɪəm hˈɑːmbleɪ, fˈaʊnd ˈoʊnli ˌɔn kˈɑːpɚ ænd nˈɪkəl kəntˈeɪnɪŋ sˈɔɪlz ɪn sˈɛntɹəl tə sˈʌðɚn ˈæfɹɪkə.
A "most faithful" indicator plant is Ocimum centraliafricanum, the "copper plant" or "copper flower" formerly known as Becium homblei, found only on copper (and nickel) containing soils in central to southern Africa.