Home » Minerals » Sillimanite

Sillimanite


Mineral Properties and Uses



Physical Properties of Sillimanite

Chemical Classification silicate
Color colorless, white, yellow, brown, blue, green
Streak colorless
Luster vitreous
Diaphaneity transparent to translucent
Cleavage perfect
Mohs Hardness 6.5 to 7.5
Specific Gravity 3.2 to 3.3
Diagnostic Properties slender crystals, fibrous habit
Chemical Composition Al2SiO5
Crystal System orthorhombic
Uses no significant commercial use


Sillimanite with magnetite
Sillimanite with magnetite from Benson Mines, New York. Specimen is approximately 4 inches (10 centimeters) across.


Sillimanite
Sillimanite from Williamstown, South Australia. Specimen is approximately 4 inches (10 centimeters) across.



Find it on Geology.com




More from Geology.com


Geology News
Geology News is displayed on the right side of our homepage and updated daily.
Homeowners Insurance
Homeowners Insurance usually does not cover the most common geologic hazards.
Asteroid Impact Map
Asteroid Impact Map: Explore fifty of the most obvious asteroid impact craters on Earth.
Sliding Rocks
Sliding Rocks Mystery: What causes these rocks to slide across a Death Valley playa?
Gem Silica
Gem Silica is a blue chalcedony colored by copper. It is the rarest and most valuable chalcedony.
Diamonds
Diamonds: Learn about the properties of diamond, its many uses and diamond discoveries.
Geo Rock Bags
Rock Bags - Durable field bags with pockets for carrying maps, books, specimens and tools.
Maw Sit Sit
Maw Sit Sit is a metamorphic rock and a gem material that was once thought be jade.


Sillimanite
Sillimanite with magnetite from Benson Mines, New York. Specimen is approximately 4 inches (10 centimeters) across.




Sillimanite
Sillimanite from Dillon, Montana. Specimen is approximately 4 inches (10 centimeters) across.


More Minerals
  Kyanite
  Minerals
  The Science of Fireworks
  Calcite
  Rock, Mineral and Fossil Collections.
  Diamond
  Fluorescent Minerals
  Hand Lens






© 2005-2016 Geology.com. All Rights Reserved.
Images, code, and content on this website are property of Geology.com and are protected by copyright law.
Geology.com does not grant permission for any use, republication, or redistribution.
Images, code and content owned by others are marked on the pages where they appear.