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  

Micaceous Minerals 3

Sunday, 19 February 2017 08:00 AM

Not all micaceous looking minerals fall in the MICA group of phyllosilicate minerals. Many of the other silicates appear micaceous but are not. We'll have a look at some of these minerals and hopefully explain the difference. Take a look at our article on Mica and Other Micaceous Minerals.

Muscovite

with Quartz - #37784
Locality
Badu Hill pegmatite, Llano Llano Co., Texas, United States 
Formula
KAl2(Si3Al)O10(OH)2 
Availability
Sold
Size
6 x 5 x 4 cm - Sm Cabinet 
Tagged
pegmatite mineral  

Very interesting 8mm "books" of Muscovite covering feldspar with a Quartz crystal at the center.


Muscovite

Formula
KAl2(Si3Al)O10(OH)2 
Crystal System
Monoclinic 
Crystal Habit
Massive - Lamellar, Foliated, Micaceous 
Cleavage
Perfect, None, None 
Luster
Vitreous (Glassy) 
Color
white, gray, silver white, brownish white, greenish white 
Streak
white 
Class
Monoclinic - Prismatic 
Fracture
Brittle - Sectile 
Hardness
2-2.5 
Collection
Art Smith Collection
Mineralpedia
View Muscovite
On Dakota Matrix
Previously Sold Muscovite
On Dakota Matrix
Other Available Muscovite
WebMineral
View Muscovite
Mindat
View Muscovite

Muscovite

var. alurgite - #BM40736
Locality
Ouro Preto, Minas Gerais, Brazil 
Formula
KAl2(Si3Al)O10(OH)2 
Availability
Sold
Size
4 x 2 x 1.5 cm - Miniature 

Alurgite is a variety of Muscovite with manganese impurity giving it the beautiful red color.


Muscovite

Formula
KAl2(Si3Al)O10(OH)2 
Crystal System
Monoclinic 
Crystal Habit
Massive - Lamellar, Foliated, Micaceous 
Cleavage
Perfect, None, None 
Luster
Vitreous (Glassy) 
Color
white, gray, silver white, brownish white, greenish white 
Streak
white 
Class
Monoclinic - Prismatic 
Fracture
Brittle - Sectile 
Hardness
2-2.5 
Collection
McConlogue Collection
Mineralpedia
View Muscovite
On Dakota Matrix
Previously Sold Muscovite
On Dakota Matrix
Other Available Muscovite
WebMineral
View Muscovite
Mindat
View Muscovite

Muscovite

var. fuchsite - #41239
Locality
Bahia, Brazil 
Formula
KAl2(Si3Al)O10(OH)2 
Availability
Sold
Size
11.5 x 8 x 2.5 cm - Cabinet 

This specimen is a large cabinet specimen with rich flashy green color exhibiting wavy foliations. It is a much richer green than appears in the photo.

Fuchsite is nothing but a Muscovite mica containing up to 4.8% chromiun (encycl. of Min.) imparting the green color and was originally described from Schwarzenstein in the Zillerthal and named after J. N. von Fuchs (Dana 6th Ed.).

Phyllosilicate - Monoclinic - Mica group member. Ordinary (True or Common) Mica - Dioctahderal. 


Muscovite

Formula
KAl2(Si3Al)O10(OH)2 
Crystal System
Monoclinic 
Crystal Habit
Massive - Lamellar, Foliated, Micaceous 
Cleavage
Perfect, None, None 
Luster
Vitreous (Glassy) 
Color
white, gray, silver white, brownish white, greenish white 
Streak
white 
Class
Monoclinic - Prismatic 
Fracture
Brittle - Sectile 
Hardness
2-2.5 
Mineralpedia
View Muscovite
On Dakota Matrix
Previously Sold Muscovite
On Dakota Matrix
Other Available Muscovite
WebMineral
View Muscovite
Mindat
View Muscovite

Muscovite

var. Star (twinned) - #43740
Locality
Jenipapo dist., Itinga, Minas Gerais, Brazil 
Formula
KAl2(Si3Al)O10(OH)2 
Availability
Sold
Size
7 x 4.5 x 4 cm - Sm Cabinet 

Twinned Muscovite crystals in star-shaped crystals to 2cm.


Muscovite

Formula
KAl2(Si3Al)O10(OH)2 
Crystal System
Monoclinic 
Crystal Habit
Massive - Lamellar, Foliated, Micaceous 
Cleavage
Perfect, None, None 
Luster
Vitreous (Glassy) 
Color
white, gray, silver white, brownish white, greenish white 
Streak
white 
Class
Monoclinic - Prismatic 
Fracture
Brittle - Sectile 
Hardness
2-2.5 
Mineralpedia
View Muscovite
On Dakota Matrix
Previously Sold Muscovite
On Dakota Matrix
Other Available Muscovite
WebMineral
View Muscovite
Mindat
View Muscovite
SOLD
Muscovite - 46688
Muscovite - 46688

Muscovite

#46688
Locality
Diamond Mica mine, Pennington Co., South Dakota, United States 
Formula
KAl2(Si3Al)O10(OH)2 
Availability
Sold
Size
8 x 5 x 0.3 cm - Sm Cabinet 
Tagged
pegmatite mineral  

A diamond shaped, natural crystal.


Muscovite

Formula
KAl2(Si3Al)O10(OH)2 
Crystal System
Monoclinic 
Crystal Habit
Massive - Lamellar, Foliated, Micaceous 
Cleavage
Perfect, None, None 
Luster
Vitreous (Glassy) 
Color
white, gray, silver white, brownish white, greenish white 
Streak
white 
Class
Monoclinic - Prismatic 
Fracture
Brittle - Sectile 
Hardness
2-2.5 
Mineralpedia
View Muscovite
On Dakota Matrix
Previously Sold Muscovite
On Dakota Matrix
Other Available Muscovite
WebMineral
View Muscovite
Mindat
View Muscovite

Muscovite

var. phengite - #PD46691
Locality
Dora Maira Massif, Cuneo prov., Piedmont, Italy 
Formula
KAl2(Si3Al)O10(OH)2 
Availability
Sold
Size
5.5 x 4 x 2 cm - Sm Cabinet 

Phengite is supposedly a high silica mica. It is a fine grained Muscovite.


Muscovite

Formula
KAl2(Si3Al)O10(OH)2 
Crystal System
Monoclinic 
Crystal Habit
Massive - Lamellar, Foliated, Micaceous 
Cleavage
Perfect, None, None 
Luster
Vitreous (Glassy) 
Color
white, gray, silver white, brownish white, greenish white 
Streak
white 
Class
Monoclinic - Prismatic 
Fracture
Brittle - Sectile 
Hardness
2-2.5 
Collection
Phillips Collection
Mineralpedia
View Muscovite
On Dakota Matrix
Previously Sold Muscovite
On Dakota Matrix
Other Available Muscovite
WebMineral
View Muscovite
Mindat
View Muscovite

All photos by Dakota Matrix and are Copyrighted © and may not be used without permission. Copyright © 2024 - Dakota Matrix Minerals, Inc. Privacy | Terms & Conditions | Site Map