Phillipsite and chabazite are natural zeolites. They are wide spread worldwide and are reported in the basic volcanic tuff. However, faujasite is only reported in few localities including Jordan. What do you think is the main reason for faujasite to be a rare natural zeolite?
In fact phillipsite and chabazite also occur in ash flow deposits and other "sedimentary" environments whereas faujasite only seems to occur in the vugs of volcanites such as phonolites and volcanic tuffs. In other words, plillipsite and chabasite also form as a result of volcanic glass transformation whereas faujasite may be considered more as a "primary" zeolite, forming directly from fluids in the vugs of volcanic rocks. Hence its occurrence is not as widespread and the quantities in which it can be found are very small.
Thanks Prof. Rinado.
Yet faujasite was recorded as a secondary zeolite mineral in an open hydrological environments (percolating water through volcanic tuff secessions) in Jordan and in California (USA).
There must be some other reasons. I might think of its complicated structure, in addition to water/rock ratio and pH.
Very interesting questions. I know faujasite from the type locality (Kaiserstuhl, Germany). Phillipsite and chabazite occur widespread in vesicles of the Kaiserstuhl volcanic complex. In contrast, faujasite occurs only in one locality (Limberg) together with phillipsite and offretite. Mg-faujasite is associated with the most primitive lavas, whereas the more evolved lavas do not contain faujasite. I assume that the fluid chemistry in addition to the fluidr-rock interaction plays a fundamental control on the formation of faujasite.
I wrote a short invited paper a few years ago, but further studies are definitely needed.: Weisenberger T. & Spürgin S. (2009) Zeolites in alkaline rocks of the Kaiserstuhl volcanic complex, SW Germany - new micropobe investigation and their relationship to the host rock. Geologica Belgica 12/1-2, 75-91 (http://popups.ulg.ac.be/1374-8505/index.php?id=2682)
Regarding reported faujasite in granites of the Swiss Alps, which is still reported in many papers. This was a misinterpretation of fluorite.
Cheers
Tobias
It is good to know that. Thank you for your answer . I will read your paper
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