Ettringite (South Africa) | Ettringite crystal, rare mineral specimenThis highly unusual piece with tiny, sparkling ettringite crystals packed together, is unlike anything else we have seen. The piece has a vibrant shade of greenish yellow, with the tiny glittering crystals creating a textured surface. The irregular shape indicates a pseudomorph, although no traces of the original mineral are visible apart from the distinctly angular faces that make up the structure of the piece. With no comparable specimens on the