System 2 - Simple binary system with a congruently melting intermediate compound.

Congruently Melting Compound - is one that when it is heated, will melt to a liquid of its own composition.

In this system the congruently melting compound produces a thermal maximum. The result is that the system can be divided into two binary diagrams, each with a simple eutectic.

Bulk compositions to the left of AB₂ will produce final solid mixtures of A and AB₂.

Bulk compositions to the right of AB₂ will produce final solid mixtures of B and AB₂.