A significant OLD-TIME locality and species specimen of this very interesting, quite rare, crystallized aluminum species. The crystals here look like cityscape blocks, lucent crystals and negative prints of disolved Siderite to 4cm associated as a very 3-dimensional and aesthetic piece. Such specimens are few and far between today, in any quality. They were mined mostly around the turn of the 1900s. The colourless material seemingly disappears in water due to the proximity of their refractive indices. Historically, Cryolite was used as an aluminum ore and later in the electrolytic processing of the aluminum ore bauxite. Ivigtut was the world´s only mine for Cryolite, used as a solvent of bauxite in aluminum production and before that to produce opaline glass. This great piece comes with 3!!! antique labels. By the way, Ivigtut is type locality for the species.