  A liquid can form under cooling a glassy state either as a result of a
continuous slowing down or by a first order polyamorphous phase transition. The
second scenario has so far always been observed below the melting point where
it interfered with crystalline nucleation. We report the first observation of
the liquid-glass transition by a first order phase transition above the melting
point. The observation was made in a molecular dynamics simulation of a
one-component system with a model metallic pair potential. This is also the
first observation of a simple monatomic ideal glass former -- a liquid that
avoids crystallization at any cooling rate. Besides its conceptual importance,
this result indicates a possibility of existence of metallic ideal glass
formers.
