Click on a letter above to view the list of gems.    

  

 


Polylithionite (inclusions in Pollucite)
Current inventory:  0 gems
 

Polylithionite in Pollucite

  
Polylithionite is named from the Greek word poly meaning many or much, in allusion to its composition with a high LITHIum content.

Discovered in 1884; IMA status: Valid (pre-IMA; Grandfathered)

 

Chemistry

 

 

Chemical Formula:

KLi2AlSi4O10 (F,OH)2

 

Potassium Lithium Aluminum Silicate Fluoride

Molecular Weight:

393.12 gm

Composition:

Potassium

9.95 %

K

11.98 %

K2O

 

Sodium

1.75 %

Na

2.36 %

Na2O

 

Lithium

3.00 %

Li

6.46 %

Li2O

 

Aluminum

6.86 %

Al

12.97 %

Al2O3

 

Silicon

28.58 %

S

61.14 %

SiO2

 

Hydrogen

0.26 %

H

2.29 %

H2O

 

Oxygen

44.77 %

O

 

 

 

Fluorine

4.83 %

F

4.83 %

F

 

 —  %

F

-2.03 %

-O=F2

 

 

100.00 %

 

100.00 %

= TOTAL OXIDE

 

 

Classification

   

   

Mineral Classification:

Silicates

Strunz 8th Ed. ID:

8/H.11-10

Nickel-Strunz 10th Ed. ID:

9.EC.20

 

9 : SILICATES (Germanates)
E : Phyllosilicates
C : Phyllosilicates with mica sheets, composed of tetrahedral and octahedral nets

Related to:

Mica Group. Polylithionite-Trilithionite Series.

Members of Group:

Mica Group: Aluminoceldonite, Anandite, Annite, Annite-Phlogopite Series, Aspidolite, Balestraite, Biotite, Bityite, Boromuscovite, Brammallite, Celadonite, Chernykhite, Chromceladonite, Chromphyllite, Clintonite, Eastonite, Ephesite, Ferroaluminoceladonite, Ferroceladonite, Ferrokinoshitalite, Fluorannite, Fluorphlogopite, Ganterite, Glauconite, Hendricksite, Illite, Kinoshitalite, Lepidolite, Luanshiweiite, Margarite, Masutomilite, Montdorite, Muscovite, Muscovite-Celadonite Series, Nanpingite, Natro-glauconite, Norrishite, Oxykinoshitalite, Oxyphlogopite, Paragonite, Phengite, Phlogopite, Polylithionite, Preiswerkite, Roscoelite, Shirokshinite, Shirozulite, Siderophyllite, Sokolovaite, Suhailite, Tainiolite, Tetraferriannite, Tetraferriphlogopite, Tobelite, Trilithionite, Voloshinite, Wonesite, Yangzhumingite, Zinnwaldite

Varieties:

Cs-bearing Polylithionite

Synonyms:

ICSD 34336 (with F), PDF 21952

 

 

Crystal Data

   

   

Crystallography:

Monoclinic - Prismatic

Crystal Habit:

Pseudohexagonal crystals, tabular || f001g, to 10 cm. As irregularly shaped aggregates of fine scaly crystals.

Twinning:

None

 

 

Physical Properties

   

 

Cleavage:

Perfect on {001} 

Fracture:

Irregular/Uneven

Tenacity:

Brittle

Moh's Hardness:

2.0 - 3.0

Density:

2.58 - 2.82 (g/cm3)

Luminescence:

May fluoresce lemon-yellow under SW UV

Radioactivity:

Barely Detectable; GRapi = 141.95 (Gamma Ray American Petroleum Institute Units)

 

 

Optical Properties

   

   

Color:

Bright to pale pink, cream to white, colorless, pale brown to yellow-brown, bluish, greenish; in transmitted light, colorless

Transparency:

Transparent

Luster:

Pearly to waxy when fine-grained

Refractive Index:

1.530 - 1.559  Biaxial ( - )

Birefringence:

0.025 - 0.029

Dispersion:

Weak

Pleochroism:

n/a

 

 

Occurances

   

   

Geological Setting:

In irregular segregations and veinlets, as a late-stage and metasomatic replacement mineral, in syenite pegmatites in a differentiated alkalic massif (Lovozero massif, Russia).

Common Associations:

Microcline, Natrolite, Taeniolite, Steenstrupine, Aegirine, Analcime, Epistolite

Common Impurities:

Ti, Fe, Mn, Mg, Ca, Na, H2O

Type Locality:

Kangerluarsuk Fjord (Kangerdluarssuq Fjord), Ilímaussaq complex, Narsaq, Kujalleq, Greenland

Year Discovered:

1884

View mineral photos:

Polylithionite Mineral Photos and Locations

 

 

More Information

   

   

 

Mindat.org
Webmineral.com

 

 


Polylithionite is named from the Greek word poly meaning many or much, in allusion to its composition with a high LITHIum content. Polylithionite is a member of the Mica Group of minerals that also includes Celadonite, Lepidolite, Muscovite  and Phlogopite. Polylithionite can often be found as attractive rosette crystal clusters resembling the petals of a flower and often associated ith Sérandite. Polylithionite is rarely available as a gemstone but a recent find in Pakistan has produced gemmy Pollucite crystals containing tiny crystal inclusions of Polylithionite. Magnification must be used to observe these tiny Polylithionite crystals which have good crystal forms. Polylithionite may fluoresce lemon yellow to pale yellowish white under shortwave UV light.

Locations for Polylithionite: On the Kangerdluarssuk Plateau and elsewhere in the Ilímaussaq intrusion, southern Greenland. In Russia, found on Mts. Karnasurt and Lepkhe-Nelm, Lovozero massif, Kola Peninsula. In the Dara-i-Pioz massif, Alai Range, Tien Shan, Tajikistan. At Vøra, Sandefjord, Oslo region, Norway. From Mont Saint-Hilaire and near Saint-Amable, Quebec, Canada. In the USA, at Point of Rocks, Colfax County, New Mexico. On Mt. Malosa, Zomba district, Malawi.
 

  
Polylithionite gems for sale:

We have not photographed our Polylithionite gems yet. Please check back soon.
 

 


I love Sarah