1. A
bulk composition of X cools to the liquidus, at which point An crystallizes.
2. Continued crystallization of An
causes liquid composition to move toward Di.
3. When T=1274°C, liquid
has moved to eutectic; Di begins to crystallize. No change in temperature or composition of any of the 3 phases
is permitted until the liquid has
completely crystallized.
4. At temperatures below 1274°C, only
crystals of An and Di are present.
X