Complex sentence: The gibbsite is usually converted into aluminium oxide, Al 2 O 3, by heating in rotary kilns or fluid flash calciners to a temperature in excess of 1000 o C. This aluminium oxide is dissolved at a temperature of about 960 ° C in molten cryolite.
Split into simpler sentences: The gibbsite is usually converted into aluminium oxide, Al 2 O 3, by heating. This mineral is dissolved at a temperature of about 960 ° C in molten cryolite.