Phillipsite - Encyclopedia

    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.

Phillipsite in the World

One of the world's best occurrences for phillipsite is Capo di Bove (Lazio, Italy) where crystals reach 1 cm. The basalts around Monument (Oregon) give crystals of 2 cm, while the red phillipsite is an Australian specialty, discovered in transparent crystals of 4 mm in the basalts of Tasmania (Liena) and Victoria (around Melbourne).


Phillipsite in France

The cavities of the basalts of the French Massif Central are sometimes lined with small phillipsite crystals : Gignat and Perrier (Puy-de-Dôme) and Espalion (Aveyron).

Twinning

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.

Fakes and treatments

No fake inventories for this mineral species.



Hardness : 4 to 4.5
Density : 2.2
Fracture : Irregular
Trace : White



TP : translucent to transparent
RI : 1.483 to 1.514
Birefringence : 0.003 to 0.009
Optical character : Biaxial +/-
Pleochroism : None
Fluorescence : None


Solubility : Hydrochloric acid

Magnetism : None
Radioactivity : None

ReCaptcha

This service is used to secure web forms of our website and required if you want to contact us. By accepting it you agree to Google's privacy policy: https://policies.google.com/privacy

Facebook

Our website allows you to like or share its content on Facebook social network. By activating and using it you agree to Facebook's privacy policy: https://www.facebook.com/policy/cookies/

YouTube

Integrated videos provided by YouTube are used on our website. By accepting to watch them you agree to Google's privacy policy: https://policies.google.com/privacy

Twitter

Integrated tweets and share services of Twitter are used on our website. By accepting and using these you agree to Twitter's privacy policy: https://help.twitter.com/en/rules-and-policies/twitter-cookies

PInterest

Our website allows you to share its content on PInterest social network. By activating and using it you agree to PInterest's privacy policy: https://policy.pinterest.com/en/privacy-policy/