There is a Kyber Crystal is hidden within Chirrut Îmwe’s Bō staff, specifically in the metal piece at the end.
The “Crystal containment lamp,” as it’s described in the Star Wars Rogue One: The Ultimate Visual Guide by Pablo Hidalgo, contains not a full Jedi Kyber Crystal, but “a kyber sliver.”
However, this doesn’t mean Chirrut is Force-sensitive, but rather the Kyber crystals known to issue a harmonic sound that typically only Jedi can hear - Chirrut, likely thanks to his blindness enhancing his hearing ability, can hear that harmonic sound.
“Likely being designed as a symbolic source of inner illumination, it also allows Chirrut to better gauge where the end of the staff is, as he can hear both the battery and crystal harmonics.”
Which is also why Chirrut was able to sense the Kyber Crystal on Jyn’s necklace - it wasn’t that he sensed it through the Force, but that he could hear the harmonic vibration of the crystal.