01

What to look for

Under 10x loupe: a transparent irregular cavity containing both a liquid phase and a gas bubble. The gas bubble appears as a round dark sphere floating within the liquid. Tilt the stone and the bubble may move.

02

What it means

Two-phase inclusions support natural origin and are formed when fluid is trapped during crystal growth. The cavity shape can reflect the host gem species.

03

Expert move

Aquamarine is famous for parallel two-phase tube inclusions that look like falling rain, oriented along the crystal axis.