mineral specimens
rare minerals
mineral dealer
systematic minerals
Black Hills minerals
fine minerals
mineral dealer
Dana minerals
IMA minerals
mineral collections
rock and minerals
gem crystal
0 item @ $0.00  

Mineralpedia Details for Pyrophyllite

Reset

Pyrophyllite

Pyrophyllite

Phyllosilicate - Monoclinic - not a Mica group member but is a member of the Talc series. Talc is found as tabular crystals {001}. foliated and stellate masses, inelastic laminae, less abundant than Talc. Forms from the alteration of Feldspars, in Al-rich rocks, under acidic conditions >300 d C...below which Kaolinite forms.

Formula
Al2Si4O10(OH)2 
Crystal System
Triclinic 
Crystal Habit
Earthy 
Cleavage
Perfect, None, None 
Luster
Pearly 
Color
brown green, brownish yellow, greenish, gray green, gray white 
Streak
white 
Class
Triclinic - Pinacoidal 
Fracture
Flexible 
Hardness
1.5-2 
WebMineral
View Pyrophyllite 
Mindat
View Pyrophyllite 

Pyrophyllite from Indian Gulch, Mariposa Co., California, United States

Pyrophyllite
            from Indian Gulch, Mariposa Co., California, United States

Phyllosilicate - Monoclinic - not a Mica group member but is a member of the Talc series. Talc is found as tabular crystals {001}. foliated and stellate masses, inelastic laminae, less abundant than Talc. Forms from the alteration of Feldspars, in Al-rich rocks, under acidic conditions >300 d C...below which Kaolinite forms.

Click thumbnail images for larger view.

Pyrophyllite from Graves Mountain, Lincoln Co., Georgia, United States

Pyrophyllite
            from Graves Mountain, Lincoln Co., Georgia, United States

Stellate groups of soft Pyrophyllite crystals in patterns 1.5cm across.

Click thumbnail images for larger view.

All photos by Dakota Matrix and are Copyrighted © and may not be used without permission. Copyright © 2025 - Dakota Matrix Minerals, Inc. Privacy | Terms & Conditions | Site Map