predominantly bitter, it would seem. q.v. "Tastes of Fifteen Halide Salts Following Water and NaCl: Anion and Cation Effects", Physiology & Behavior 26:1083-1109, https://sci-hub.se/https://doi.org/10.1016/0031-9384(81)90213-4
Also thank you for saving me from an argument when I ate cesium (and also heavy metal poisoning/radiation poisoning depending on the isotope).
=D did you know that there was once a fad for cesium chloride as a "dietary supplement" because of some idea that it was good for treating cancer? I think the fad died, but you used to be able to get CsCl in capsules on Amazon or wherever—like, actual CsCl and not some homeopathic preparation.
