- Chert (/ˈtʃɜːrt/) is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a chemical precipitate or a diagenetic replacement, as in petrified wood.
- Talitha (stars.astro.illinois.edu)
TALITHA (Iota Ursae Majoris). Three close (but physically unrelated) pairs of stars make the feet of Ursa Major, the Great Bear. In Arabic culture, the three represent the “leaps” of a gazelle, Talitha (Bayer’s “Iota” star) and Kappa Ursae Majoris making (and meaning) the westernmost “third leap” (the name actually coming from the number 3).