ðə lˈɪθiəm ɐlˈuːmᵻnˌeɪt lˈeɪɚɹ ɪz ɪnsˈɑːljuːbəl ɪn sᵻmˈɛnt pˈoːɹ wˈɔːɾɚ ænd pɹətˈɛkts ðɪ ˌʌndɚlˈaɪɪŋ ˌæljʊmˈɪniəm ˈɑːksaɪd kˈʌvɚɹɪŋ ðə mətˈælɪk ˌæljʊmˈɪniəm fɹʌm dˌɪsəlˈuːʃən æt hˈaɪ pˈiː ˈeɪtʃ. ɪɾ ɪz ˈɔːlsoʊ ɐ pˈoːɹ fˈɪlɚ.
The lithium aluminate layer is insoluble in cement pore water and protects the underlying aluminium oxide covering the metallic aluminium from dissolution at high pH. It is also a pore filler.