Class : Silicates
    Subclass : Tectosilicates
    Crystal system : Monoclinic
    Chemistry : KCaAl₃Si₅O₁₆ 6H₂O
    Rarity : Uncommon

Phillipsite belongs to the group of zeolites and more particularly to the family of pseudocubic zeolites. It owes its name to William Phillips, one of the founding geologists and mineralogists of the Geological Society of London. It is a frequent zeolite in the cracks and cavities of basic and ultrabasic rocks, notably basalts, known (but rarer) in the deposits of salt lakes and hot springs. Sometimes colorless, phillipsite is commonly white, sometimes reddish. Along with chabazite and harmotome, phillipsite is a good molecular sieve, a major industrial property used in hydrocarbon refining, deriving from the channel structure of zeolites.

Main photo : Phillipsite from Rossberg Quarry, Hesse, Germany © Volker Betz

The phillipsite is always twinned in a more or less complex way associating two, four, eight or twelve crystals, and simulating tetragonal buildings, themselves grouped into rhombododecahedral buildings in a cross.

No fake inventories for this mineral species.