Calcium sulfate an unusual property: when mixed with water at normal (ambient) temperatures, it quickly reverts chemically to the preferred dihydrate form, while physically "setting" to form a rigid and relatively strong gypsum crystal lattice: This reaction is exothermic and is responsible for the ease with which gypsum can be cast into various shapes including sheets (for drywall), sticks (for blackboard chalk), and molds (to immobilize broken bones, or for metal casting). Mixed with polymers, it has been used as a bone repair cement. Small amounts of calcined gypsum are added to earth to create strong structures directly from cast earth, an
Rock Chalk, Jayhawk preceded by the Kansas alma mater "Crimson and the Blue,” and followed by the fight song, "I'm a Jayhawk.” Since the early 1990's, Kansas fans have been known to do the slow repetition of "Rock chalk... Jay-Hawk... KU" when the Jayhawks are believed to be safely ahead, and victory is guaranteed. Rock Chalk, Jayhawk "Rock Chalk, Jayhawk" (a.k.a. the "Rock Chalk" chant) is a chant used at University of Kansas Jayhawks sporting events. The chant is made up of the phrase "Rock chalk, Jayhawk, KU". The chant was first adopted by the university's science club in 1886. Chemistry professor E.H.S.