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(n.)
A niobate of calcium, cerium, and other bases, occurring usually in octahedrons of a yellowish or brownish color and resinous luster; -- so called from its becoming grass-green on being subjected to heat under the blowpipe.
  

General Information:
 Chemical Formula:
(Na,Ca)2Nb2O6(OH,F)
 Composition:
(Molecular Weight = 353.84 gm)
Sodium 9.75 % Na
Calcium 5.66 % Ca
Niobium 52.51 % Nb
Hydrogen 0.21 % H 
Oxygen 30.52 % O 
Fluorine 1.34 % F 
 Empirical Formula:
Na1.5Ca0.5Nb2O6(OH)0.75F0.25
 Environment:
Nepheline-syenite rocks.
 IMA Status:
Approved IMA 1977
 Locality:
Fredriksvarn and Larvik, Norway.
 Name Origin:
From the Greek pyr - "fire" and chloros - "green."
Physical Properties:
 Cleavage:
[111] Indistinct, [111] Indistinct, [111] Indistinct
 Color:
brown, yellowish brown, yellow, greenish brown, or reddish brown.
 Density:
4.2 - 6.4, Average = 5.3
 Diaphaniety:
Subtranslucent to opaque
 Habits:
Granular - Generally occurs as anhedral to subhedral crystals in matrix., Disseminated - Occurs in small, distinct particles dispersed in matrix.,
 Hardness:
5-5.5 - Apatite-Knife Blade
 Luminescence:
None.
 Luster:
Resinous - Greasy
 Streak:
yellowish brown
More details...

B: (Kimia) piroklor

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See more at Wikipedia.org...

(n.)
A niobate of calcium, cerium, and other bases, occurring usually in octahedrons of a yellowish or brownish color and resinous luster; -- so called from its becoming grass-green on being subjected to heat under the blowpipe.
  

General Information:
 Chemical Formula:
(Na,Ca)2Nb2O6(OH,F)
 Composition:
(Molecular Weight = 353.84 gm)
Sodium 9.75 % Na
Calcium 5.66 % Ca
Niobium 52.51 % Nb
Hydrogen 0.21 % H 
Oxygen 30.52 % O 
Fluorine 1.34 % F 
 Empirical Formula:
Na1.5Ca0.5Nb2O6(OH)0.75F0.25
 Environment:
Nepheline-syenite rocks.
 IMA Status:
Approved IMA 1977
 Locality:
Fredriksvarn and Larvik, Norway.
 Name Origin:
From the Greek pyr - "fire" and chloros - "green."
Physical Properties:
 Cleavage:
[111] Indistinct, [111] Indistinct, [111] Indistinct
 Color:
brown, yellowish brown, yellow, greenish brown, or reddish brown.
 Density:
4.2 - 6.4, Average = 5.3
 Diaphaniety:
Subtranslucent to opaque
 Habits:
Granular - Generally occurs as anhedral to subhedral crystals in matrix., Disseminated - Occurs in small, distinct particles dispersed in matrix.,
 Hardness:
5-5.5 - Apatite-Knife Blade
 Luminescence:
None.
 Luster:
Resinous - Greasy
 Streak:
yellowish brown
More details...

B: (Kimia) piroklor

Built to Babylon by Hikmat Gumilar
 Visit my Website;