Ultrasonic investigation of the first-order α-β phase transition in quartz

Elastic constants and ultrasonic attenuation of quartz are reported near the α-β phase transition. The data allow the conclusion that the transition is of first order. The critical elastic constant c14 depends on temperature as c14(T) - c14(Tα) = const. (T - T) 1 2 and the stability limit for the α phase is Tα = 579°C. © 1970.