At what temperature is alumina calcined during aluminum refining?

During the Bayer process of aluminum refining, aluminum hydroxide crystals are calcined in rotary kilns or stationary fluidized-bed flash calciners at temperatures exceeding 960 °C (1,750 °F) to drive off free and chemically combined water.1

While this general calcination process occurs above 960 °C, the specific product known as "calcined alumina"—which is heated to remove nearly all chemically combined water—is typically processed at temperatures in excess of 1,050 °C (1,900 °F).2