B 61 Geology of the Stone Mountain Lithonia District Georgia

phengite and 11 ferrimuscovite Biotite is pleochroic from X light found in abundance on the northwest side of Stone Mountain The pegmatites are Crushing strength tests made on Lithonia gneiss and Stone Mountain granite at the

phengite 3t in high pressure metamorphosed granitic RRuff

7 and 27Vo of CaAlSiO4F Keywords phengite 3T celadonite rich muscovite granitic and Cape Nome sam ples and more abundant in those from Kiwalik

Phengite Wikipedia

Phengite is a series name for dioctahedral micas of composition K AlMg 2 OH 2 SiAl 4O10 similar to muscovite but with addition of magnesium It is a non IMA

Phengite Mineral information data and localities Mindat

Phengite is an aluminous true mica which contains a relatively high amount of tetrahedrally co ordinated Si gt 3 1 apfu As the Si amount increases

The Biotite to Phengite Reaction and Mica dominated CiteSeerX

occurs through the reactions phengite or biotite юzoisite юquartz coesite юfluid ¼silicate abundance of hydrates and an increase of carbonates in the solid

Compositional and structural relationships between phengites and

Jan 12 1970 INTRODUCTION THE NATURE of illite as a monomineral phase has been recently discussed by Gaudette Eades and Grim 1966