Silicates are very detrimental to steels, especially if it has to undergo heat treatment at a later stage.
sˈɪlᵻkˌeɪts ɑːɹ vˈɛɹi dˌɛtɹɪmˈɛntəl tə stˈiːlz, ɪspˈɛʃəli ɪf ɪt hɐz tʊ ˌʌndɚɡˈoʊ hˈiːt tɹˈiːtmənt æɾə lˈeɪɾɚ stˈeɪdʒ.