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
Gordon Chalk Mansfield swore in Chalk as Premier on 1 August, pending the Country Party electing a new leader. They chose Joh Bjelke-Petersen, who succeeded Chalk after a week in office. Chalk continued as Treasurer and Leader of the Liberal Party until his resignation from parliament in 1976. In the Queen's Birthday Honours of June 1971, he was made a Knight Commander of the Order of the British Empire (KBE). Upon his death in 1991 Chalk was accorded a State funeral which was held at Albert Street Uniting Church and he was later cremated. Gordon Chalk Sir Gordon William Wesley Chalk, (16