phase separation

https://doi.org/10.1351/goldbook.P04534
The process by which a single solid (liquid) phase separates into two or more new phases.
Source:
PAC, 1994, 66, 577. 'Definitions of terms relating to phase transitions of the solid state (IUPAC Recommendations 1994)' on page 588 (https://doi.org/10.1351/pac199466030577)