Transparency Crystals are translucent and rarely transparent. Crystal Habit is usually massive but rare crystals are found in flattened tabular crystals. In many bauxite specimens gibbsite is found in a pisolitic habit. Also found as botryoidal encrustations, concretionary, stalactitic and foliated masses. Cleavage is perfect in one direction, basal.
Fracture is uneven.
Streak is white. Associated Minerals are boehmite , diaspore , azurite , hydrozincite and aurichalcite . Best Field Indicators are crystal habits, hardness, smell and associations.