Many cobaltocenium salts coprecipitate with caesium salts, and cobaltocenium hydroxide is a strong base that absorbs atmospheric carbon dioxide to form cobaltocenium carbonate.
mˈɛni kˌoʊbɐltˈoʊsniəm sˈɔlts kˌɑːpɹɪsˈɪpᵻtˌeɪt wɪð sˈiːsiəm sˈɔlts, ænd kˌoʊbɐltˈoʊsniəm haɪdɹˈɑːksaɪd ɪz ɐ stɹˈɔŋ bˈeɪs ðæt ɐbsˈoːɹbz ˌætməsfˈɛɹɪk kˈɑːɹbən daɪˈɑːksaɪd tə fˈɔːɹm kˌoʊbɐltˈoʊsniəm kˈɑːɹbənˌeɪt.