Complex sentence: Aluminium oxide has a melting point of over while pure cryolite has a melting point of; a small percentage of aluminium oxide dissolved in cryolite has a melting point of about.
Split into simpler sentences: Aluminium oxide has a melting point of over while pure cryolite has a melting point of. With a small percentage of alumina dissolved in it, cryolite has a melting point of about.