Recently Released Special Editions
Systematic Micaceous Minerals
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
- Sold
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- Locality
- Lengenbach quarry, Binn Valley, Wallis, Switzerland
- Formula
- KAl2(Si3Al)O10(OH)2
- Availability
- Sold
- Size
- 7 x 5 x 3 cm - Sm Cabinet
Phyllosilicate - Monoclinic - Mica group member. Ordinary (True or Common) Mica - Dioctahderal.
This locality demonstrates the diversity in which Muscovite occurs. At Lengenbach, hydrothermal mineralization of base metals occured in Triassic dolostones in which at least 130 minerals (Mindat) have been identified. Muscovite being just incidental to tht overall selection of rare sulfides and sulfosalts.
On this piece, Muscovite crystals occur as slightly pale green platy crystals.
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
Muscovite
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- Locality
- Franklin, Sussex Co., New Jersey, United States
- Formula
- KAl2(Si3Al)O10(OH)2
- Availability
- Sold
- Size
- 11 x 6 x 1.5 cm - Cabinet
Phyllosilicate - Monoclinic - Mica group member. Ordinary (True or Common) Mica - Dioctahderal.
Large dep brown foliated plate of Muscovite, although this one could easily be Hendricksite of a Biotite.
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
Muscovite
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- Locality
- Warren Brothers quarry, Bristol Co., Massachusetts, United States
- Formula
- KAl2(Si3Al)O10(OH)2
- Availability
- Sold
- Size
- 10 x 7 x 3 cm - Cabinet
Phyllosilicate - Monoclinic - Mica group member. Ordinary (True or Common) Mica - Dioctahderal.
This specimen contains hundreds of pseudohexagonal platy crystals to 7-10mm.
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
Norrishite
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- Locality
- Hoskins mine, Grenfell, Forbes Co., New South Wales, Australia
- Formula
- KLiMn3+2[O2| Si4O10]
- Availability
- Sold
- Size
- 2 x 1 x 1 cm - Thumbnail
- Special Info
- Type Locality
Phyllosilicate - Monoclinic - Mica group member. Ordinary (True or Common) Mica - Dioctahderal with Lithium and trivalent Mn.
Occurs as shiny black flakes to 1.5mm which are translucent to opaque. In rock forming oxidized, Mn-rich silicate rock (Bernard & Hyrsl). Mindat list 4 localities worlwide.
Norrishite
- Formula
- KLiMn3+2Si4O12
- Crystal System
- Monoclinic
- Crystal Habit
- Foliated, Massive
- Cleavage
- Perfect, None, None
- Luster
- Sub Metallic
- Color
- brownish black, black
- Streak
- light brown
- Class
- Monoclinic - Prismatic
- Hardness
- 2.5
- Collection
- Phillips Collection
- Special Info
- Type Locality
- Mineralpedia
- View Norrishite
- On Dakota Matrix
- Previously Sold Norrishite
- On Dakota Matrix
- Other Available Norrishite
- WebMineral
- View Norrishite
- Mindat
- View Norrishite
