Gibbsite

Gibbsite, Al(OH)₃, is one of the mineral forms of aluminium hydroxide. It is often designated as γ-Al(OH)₃ (but sometimes as α-Al(OH)₃).^[1] It is also sometimes called hydrargillite (or hydrargyllite). It is an important ore of aluminium, and one of the main parts of the rock Bauxite.

Gibbsite
Gibbsite from Brazil
General
Category	Hydroxide minerals
Formula (repeating unit)	Al(OH)3
Strunz classification	04.FE.10