GMELINITE-Ca (miniature) on ANALCIME, Little Plains, Quarry Blue Tier, Weldborough, Tasmania

Gmelinite comprises a group of rare zeolite minerals, with gmelinite-Na being the most prevalent variant, alongside gmelinite-Ca and gmelinite-K. This mineral is closely associated with chabazite, another zeolite. First identified as a distinct species in 1825, gmelinite was named in honor of Christian Gottlob Gmelin, a German chemist and mineralogist, and was later classified as a series in 1997. Gmelinite-Na can be synthesized from sodium-rich aluminosilicate gels. The natural form of gmelinite is characterized by striking crystals that take the shape of shallow, six-sided double pyramids, exhibiting a range of colors including colorless, white, pale yellow, greenish, orange, pink, and red, often likened to angular flying saucers.