title_body: Which character is best to use for a schwa? Ь or Ъ?
upvoted_answer: If you're going to use one of &lt;ъ&gt; or &lt;ь&gt; to represent /ə/, it's probably better to use &lt;ъ&gt;. This letter is currently used to write /ɤ/ in modern Bulgarian, whereas &lt;ь&gt;, as far as I'm aware, is only used to write actual vowels in dead Slavic languages. Moreover, because &lt;ь&gt; historically represented a short front vowel, it is used in modern languages like Russian to indicate palatalisation, something that does not accompany /ə/, whereas, e.g. in both modern (and more widely in pre-reform) Russian, &lt;ъ&gt; marks not a vowel but the absence of palatalisation.