Aubrey Tigan is a renowned carver and has been making riji since he was initiated at the age of 21. Riji are a form of body adornment that are used to cover male genitalia; they are worn by young men after several stages of initiation, but prior to them being fully initiated. The riji's geometric designs relay cultural knowledge and the insights their makers have received in dreams from their spirit guides.

To the Bardi people, pearl shells signify ‘water’ — their shimmering casings evoke the lightning that precedes summer storms. Riji thus hold great significance for the Bardi, who associate the elaborately engraved pearl-shell pendants with rain-making rituals. Water, rain and lightning — all factors in the seasonal reawakening of the land after long dry periods — are embodied in the shell. Shells are often engraved at the end of each year in the humid conditions that precede the wet season, as it is thought that moist air softens the shells.

Tigan uses a dremel (electric jeweller’s tool) to incise the smooth inner surface of his pearl shells with patterns that he fills with red ochre to emphasise his designs.