Due to planetary differentiation, the core region is believed to be primarily composed of iron (88.8%), with smaller amounts of nickel (5.8%), sulfur (4.5%), and less than 1% trace elements.
dˈuː tə plˈænɪtˌɛɹi dˌɪfɚɹˌɛnʃɪˈeɪʃən, ðə kˈoːɹ ɹˈiːdʒən ɪz bᵻlˈiːvd təbi pɹaɪmˈɛɹᵻli kəmpˈoʊzd ʌv ˈaɪɚn ˈeɪɾi ˈeɪt.ˈeɪt pɚsˈɛnt, wɪð smˈɔːlɚɹ ɐmˈaʊnts ʌv nˈɪkəl fˈaɪv.ˈeɪt pɚsˈɛnt, sˈʌlfɜː fˈoːɹ.fˈaɪv pɚsˈɛnt, ænd lˈɛs ðɐn wˈʌn pɚsˈɛnt tɹˈeɪs ˈɛlɪmənts.