Mindat Logo
Home Page Log In Message Board The Mindat Directory
Register Search Pages Mineral Chatroom The Mindat Store

Selwynite

This page is currently not sponsored. Click here to sponsor this page.
Big Photo

Wycheproof granite quarry, Wycheproof, Victoria, Australia
© Knut Eldjarn

Show Selwynite Photos (4)



Formula:
NaK(Be,Al)Zr
 
2
(PO
 
4
)
 
4
 · 2H
 
2
O
System:TetragonalColour:Deep purplish blue
Lustre:VitreousHardness:4
Member of:Gainesite Group
Name:For A. R. C. Selwyn (1824-1902), founding director of the Geological Survey of Victoria, Australia.


Gainesite Group

Classification of Selwynite

IMA status:Approved
Strunz 8th edition ID:7/C.02-25
Nickel-Strunz 10th (pending) edition ID:8.CA.20

8 : PHOSPHATES, ARSENATES, VANADATES
C : Phosphates without additional anions, with H2O
A : With small and large/medium cations
Dana 8th edition ID:40.5.4.3

40 : HYDRATED NORMAL PHOSPHATES,ARSENATES AND VANADATES
5 : AXO4·xH2O
mindat.org URL:http://www.mindat.org/min-7287.html
Please feel free to link to this page.

Type Occurrence of Selwynite

Type Locality:Wycheproof granite quarry, Wycheproof, Victoria, Australia
Year of Discovery:1995

Physical Properties of Selwynite

Lustre:Vitreous
Diaphaneity (Transparency):Transparent, Translucent
Colour:Deep purplish blue
Streak:Lavender, pale
Hardness (Mohs):4

Crystallography of Selwynite

Crystal System:Tetragonal
Cell Parameters:a = 6.57Å, c = 17.14Å
Ratio:a:c = 1 : 2.609
Unit Cell Volume:V 739.85 ų (Calculated from Unit Cell)

Optical Data of Selwynite

Type:Uniaxial (+)
RI values: nω = 1.624 nε = 1.636
Maximum Birefringence:δ = 0.012

Chart shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:Moderate

Chemical Properties of Selwynite

Formula:
NaK(Be,Al)Zr
 
2
(PO
 
4
)
 
4
 · 2H
 
2
O
Essential elements:Be, H, K, Na, O, P, Zr
All elements listed in formula:Al, Be, H, K, Na, O, P, Zr
Common Impurities:Rb,Ca,Sr,Ba,Mg,Mn,Fe,Cs,Ce,Hf,P,Si,F

Relationship of Selwynite to other Species

Member of:Gainesite Group
Other Members of Group:

- +
Gainesite
Na(Na,K)(Be,Li)Zr
 
2
(PO
 
4
)
 
4
 · 1.5-2H
 
2
O
Mccrillisite
NaCs(Be,Li)Zr
 
2
(PO
 
4
)
 
4
 · 1-2H
 
2
O
Related Minerals - Nickel-Strunz Grouping):

- +
8.CA.05Fransoletite
Ca
 
3
Be
 
2
(PO
 
4
)
 
2
(HPO
 
4
)
 
2
 · 4H
 
2
O
8.CA.05Parafransoletite
Ca
 
3
Be
 
2
(PO
 
4
)
 
2
(HPO
 
4
)
 
2
 · 4H
 
2
O
8.CA.10Ehrleite
Ca
 
4
Be
 
3
Zn
 
2
(PO
 
4
)
 
6
 · 9H
 
2
O
8.CA.15Faheyite
(Mn,Mg,Na)Be
 
2
Fe
 
2
(PO
 
4
)
 
4
 · 6H
 
2
O
8.CA.20Gainesite
Na(Na,K)(Be,Li)Zr
 
2
(PO
 
4
)
 
4
 · 1.5-2H
 
2
O
8.CA.20Mccrillisite
NaCs(Be,Li)Zr
 
2
(PO
 
4
)
 
4
 · 1-2H
 
2
O
8.CA.25Pahasapaite
Li
 
8
(Ca,Li,K)
 
10.5
Be
 
24
(PO
 
4
)
 
24
 · 38H
 
2
O
8.CA.30Hopeite
Zn
 
3
(PO
 
4
)
 
2
 · 4H
 
2
O
8.CA.35Warikahnite
Zn
 
3
(AsO
 
4
)
 
2
 · 2H
 
2
O
8.CA.40Phosphophyllite
Zn
 
2
Fe(PO
 
4
)
 
2
 · 4H
 
2
O
8.CA.45Parascholzite
CaZn
 
2
(PO
 
4
)
 
2
 · 2H
 
2
O
8.CA.45Scholzite
CaZn
 
2
(PO
 
4
)
 
2
 · 2H
 
2
O
8.CA.50Keyite
Cu
2+
3
Zn
 
4
Cd
 
2
(AsO
 
4
)
 
6
 · 2H
 
2
O
8.CA.55Pushcharovskite
K
 
0.6
Cu
 
18
(AsO
 
4
)(HAsO
 
4
)
 
10
(H
 
2
AsO
 
4
)
 
4
(OH)
 
9.6
·18.6H
 
2
O
8.CA.60Prosperite
CaZn
 
2
(AsO
 
4
)(HAsO
 
4
)(OH)
8.CA.65Gengenbachite
KFe
3+
3
(HPO
 
4
)
 
4
(H
 
2
PO
 
4
)
 
2
 · 6H
 
2
O
8.CA.70Parahopeite
Zn
 
3
(PO
 
4
)
 
2
 · 4H
 
2
O

Other Names for Selwynite

Synonyms:
IMA1993-037Potassian Gainesite
Other Languages:
German:Selwynit
Spanish:Selwynita

Other Information

Health Warning:No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

References for Selwynite

Reference List:

- +
Birch, W.D. and D.A.Henry (1993), Phosphate Minerals of Victoria: 39.

Birch, W. D., Pring, A. & Foord, E. E. (1995): Selwynite, NaK(Be,Al)Zr2(PO4)4.2H2O, a new gainesite-like mineral from Wycheproof, Victoria, Australia. Canadian Mineralogist: 33: 55-58.

Mineralogical Record: 27: 120.


Internet Links for Selwynite

Search Engines:
  • Look for Selwynite on Google
  • Look for Selwynite images on Google
    • External Links:
  • Look for Selwynite on Webmineral
  • Look for Selwynite on Athena Mineralogy
  • Look for Selwynite on Mineralien Atlas
  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Selwynite details from Handbook of Mineralogy (PDF)
    • Mineral Dealers:
  • Find Selwynite on www.crystalclassics.co.uk
  • Mineral Classics - Worldwide Collector Quality Minerals and Gems
  • Edwards Minerals - Fine Specimens
  • Buy fine minerals and gemstones from Pala International
  • Search for - Selwynite - on e-Rocks Mineral Sales & Auctions
  • High-end worldwide specimens & outstanding customer service
  • Pricedownminerals.com - Reverse Auctions and Shop
  • Wilensky Fine Minerals
  • Fine Minerals from Weinrich Minerals, Inc.
  • Fabre Minerals - search for Selwynite specimens
  • Buy from David K Joyce minerals
  • Rare and Unusual minerals at Mineralogical Research Company
    • Jobs:
  • Mining & Geology Jobs

    • Localities for Selwynite

    The map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
    Hide Locality List
    (TL) indicates type locality. ? indicates mineral may be doubtful at this locality. All other localities listed without reference should be considered as uncertain and unproven until references can be found.
    Australia
     
    • Victoria
    No reference listed
      • Wycheproof
    		CM 1995, 55-8
    Mineral and/or Locality
    Search Google
     
    Copyright © Jolyon Ralph and Ida Chau 1993-2011. Site Map. Locality, mineral & photograph data are the copyright of the individuals who submitted them. Further information contact the Site hosted & developed by Jolyon Ralph. Mindat.org is an online information resource dedicated to providing free mineralogical information to all. Mindat relies on the contributions of hundreds of members and supporters. Mindat does not offer minerals for sale. If you would like to add information to improve the quality of our database, then click here to register.
    Current server date and time: 13th Sep 2011 13:47:51
    Mineral and Locality Search
    Mineral:
    and/or Locality:
    Options
    Fade toolbar when not in focusFix toolbar to bottom of page
    Hide Social Media Links
    Slideshow frame delay seconds