Blockstream Jade Bip39. The only real rationale These letters are listed is to make it easier for our human brains to study them and possibly memorize our recovery phrase. As you could see, these are typically regular words which are very easy to shop or don't forget. It's not at https://rowankueqz.thebindingwiki.com/7794454/the_anatomy_of_a_bip39_phrase_entropy_text_and_stability