Chemical differences among the serpentine "polymorphs'
Chemical differences among the serpentine "polymorphs'
American Mineralogist (October 1968) 53 (1-2): 201-215
- antigorite
- chrysotile
- clay minerals
- composition
- crystal chemistry
- crystal structure
- crystallography
- experimental studies
- kaolinite
- lizardite
- major-element analyses
- mineral data
- mineralogy
- serpentine
- serpentine group
- sheet silicates
- silicates
- zeolite
- Serpentines
- kaolinite synthesis
- synthesis from zeolites
- polymorphism questioned
- chrysotile-lizardite-antigorite
Existing wet chemical analyses and structural studies of the serpentine minerals, chrysotile, lizardite, and antigorite suggest that these minerals have different chemical compositions and could be identified by composition alone. Triangular composition diagrams, a statistical treatment of the oxide components, MgO, FeO, Fe (sub 2) O (sub 3) , Al (sub 2) O (sub 3) , and H (sub 2) O, and calculated mineral formulae from chemical analyses all suggest that chrysotile, lizardite, and antigorite are not polymorphs. Antigorite is distinguished by its comparatively low H (sub 2) O and high SiO (sub 2) contents. Chrysotile is characterized by a relatively high H (sub 2) O and MgO content and by a small ratio of Fe (sub 2) O (sub 3) to FeO; while lizardite has high SiO (sub 2) and low FeO contents.
