Phase transitions surround us—for instance, liquid water changes to ice when frozen and to steam when boiled. Now, researchers at the Carnegie Institution for Science have discovered a new phenomenon of so-called metastability in a liquid phase. A metastable liquid is not quite stable. This state is common in supercooled liquids, which are liquids that cool below the freezing point without turning into a solid or a crystal. Now, scientists report the first experimental evidence of creating a metastable liquid directly by the opposite approach: melting a high-pressure solid crystal of the metal bismuth via a decompression process below its melting point.