Gibbsite is a relatively rare aluminum hydroxide. It is composed of two different color phases: a rich blue and a lighter sky blue with individual azur botryoidal spheres around 2.5mm. Gibbsite from this relatively new find (2012) in Yunnan Province represent some of the most colorful specimens of this uncommon species. It is surprisingly lightweight, and very fragile.
It appears that broken crystals, or ones with thin "shells?" fluoresce blue while most is fluorescent green. Under LW everything shifts to a whitish blue. SW and LW shown, followed by a gallery of closeups, white light pics and size.