All of the discovered alkali metals occur in nature as their compounds: in order of abundance, sodium is the most abundant, followed by potassium, lithium, rubidium, caesium, and finally francium, which is very rare due to its extremely high radioactivity; francium occurs only in minute traces in nature as an intermediate step in some obscure side branches of the natural decay chains.
ˈɔːl ʌvðə dɪskˈʌvɚd ˈælkəlˌaɪ mˈɛɾəlz əkˈɜːɹ ɪn nˈeɪtʃɚɹ æz ðɛɹ kˈɑːmpaʊndz: ɪn ˈɔːɹdɚɹ ʌv ɐbˈʌndəns, sˈoʊdiəm ɪz ðə mˈoʊst ɐbˈʌndənt, fˈɑːloʊd baɪ pətˈæsiəm, lˈɪθiəm, ɹuːbˈɪdiəm, sˈiːsiəm, ænd fˈaɪnəli fɹˈænsiəm, wˌɪtʃ ɪz vˈɛɹi ɹˈɛɹ dˈuː tʊ ɪts ɛkstɹˈiːmli hˈaɪ ɹˌeɪdɪoʊæktˈɪvᵻɾi; fɹˈænsiəm əkˈɜːz ˈoʊnli ɪn mˈɪnɪt tɹˈeɪsᵻz ɪn nˈeɪtʃɚɹ æz ɐn ˌɪntɚmˈiːdiət stˈɛp ɪn sˌʌm əbskjˈʊɹ sˈaɪd bɹˈæntʃᵻz ʌvðə nˈætʃɚɹəl dᵻkˈeɪ tʃˈeɪnz.