Product Code Database
Example Keywords: super mario -wheels $77-193
   » » Wiki: Glaucophane
Tag Wiki 'Glaucophane'.
Tag
20%

Glaucophane is a and a mineral group belonging to the sodic supergroup of the double chain inosilicates, with the chemical formula Na2(Mg3Al2)Si8O22(OH)2.

Glaucophane crystallizes in the monoclinic system.


Name
Glaucophane is named for its typical blue color. In , glaucophane means "blue appearing". As the major mineral component, it is glaucophane's color that gives the "" type its name.


Characteristics
The blue color is very diagnostic for this species. Glaucophane, along with the closely related mineral , to which it forms a series with, and their intermediate , are the only well known that are commonly blue. Glaucophane forms a series with (). Glaucophane is the -rich and ferroglaucophane is the -rich endmember.

Ferroglaucophane is similar to glaucophane but is slightly denser and hence increased . The two endmembers are indistinguishable in hand specimens and are strongly . Glaucophane's is 5–6 and its specific gravity is approximately 3–3.2.


Occurrence
The blueschist metamorphic facies gets its name from abundant blue minerals glaucophane and . Glaucophane generally forms in blueschist metamorphic rocks of gabbroic or basaltic composition that are rich in and have experienced low temperature-high pressure such as would occur along a zone.

This material has undergone intense pressure and moderate heat as it was subducted downward toward the mantle. Glaucophane is also found in that have undergone retrograde metamorphism.

There is also a rare amphibole called , chemical formula Li2Mg3Al2Si8O22(OH)2, which occurs only in lithium-rich continental rocks. For many years, holmquistite was mistaken for glaucophane, as the two look identical in thin section.


See also
  • List of Minerals


External links
Page 1 of 1
1
Post Comment
Font Size...
Font Family...
Font Format...

Page 1 of 1
1

Account

Social:
Pages:  ..   .. 
Items:  .. 

Navigation

General: Atom Feed Atom Feed  .. 
Help:  ..   .. 
Category:  ..   .. 
Media:  ..   .. 
Posts:  ..   ..   .. 

Statistics

Page:  .. 
Summary:  .. 
1 Tags
10/10 Page Rank
5 Page Refs