349 - Gismondine-Ca

ID	349
Mineral	Gismondine-Ca
Location	Arensberg - Zilsdorf - Rhineland-Palatinate - Germany
Fluorescence	LW-UV: close SW-UV: close
Mindat.org	View Gismondine-Ca information at mindat.org

ID	1701
Long ID	1:1:1701:1
Formula	`Ca₂(Si₄Al₄)O₁₆ · 8H₂O`
IMA Status	0
Diapheny	Transparent,Translucent
Cleavage	Two poor to distinct cleavages parallel to form {_232}.
Colour	Colorless, white, grayish, bluish white, reddish
Hardness (min)	4.5
Hardness (max)	4.5
About the name	Named gismondine in 1817 for Carlo Giuseppe Gismondi (1762-1824), Italian mineralogist, who previously discovered "zeagonite" - a mixture of gismondine and phillipsite. The suffix was added by the IMA in 2021, after the discovery of gismondine-Sr. The suffix/modifier follows the naming convention for zeolites and denotes the dominant extra-framework cation.
Streak	White
Crystal System	Monoclinic
Cleavage Type	Distinct/Good
Fracture type	Conchoidal,Sub-Conchoidal
Morphology	Simple pseudotetragonal dipyramids.
Twinning	Very common
Publication Year	1817
shortcode_ima	Gis
Group	Gismondine Subgroup

Gismondine-Ca