Mindat Logo
Home Page Log In Message Board The Mindat Directory
Register Search Pages Chat Now! (2 online) Mindat Auctions

Armstrongite

Big Photo

Dorozhnyi pegmatite, Khan Bogdo (Khan-Bogdinskii) massif, Gobi Desert, Mongolia
© Pavel M. Kartashov

Show Armstrongite Photos (4)
Formula:
CaZr[Si
 
6
O
 
15
]·3H
 
2
O
System:MonoclinicColour:Dark to light brown
Hardness:4½
Name:
Named after Neil Armstrong (1930-), American astronaut, who landed on the moon..
This page provides mineralogical data about Armstrongite.

Classification of Armstrongite

IMA status:Approved
Strunz 8th edition ID:8/H.34-70
Nickel-Strunz 10th (pending) edition ID:9.EA.35

9 : SILICATES (Germanates)
E : Phyllosilicates
A : Single nets of tetrahedra with 4-, 5-, (6-), and 8-membered rings
Dana 8th edition ID:72.5.4.1

72 : PHYLLOSILICATES Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings
5 : Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings with corrugated and complex layers
Hey's CIM Ref.:14.10.22

14 : Silicates not Containing Aluminum
10 : Silicates of Zr or Hf
mindat.org URL:http://www.mindat.org/min-344.html
Please feel free to link to this page.

Type Occurrence of Armstrongite

Type Locality:Khan Bogdo (Khan-Bogdinskii) Massif, Gobi Desert, Mongolia
Place of Conservation of Type Material:Fersman Museum
Year of Discovery:1973

Occurrences of Armstrongite

Geological Setting:Alkalic granites

Physical Properties of Armstrongite

Lustre:Vitreous
Diaphaneity (Transparency):Translucent
Colour:Dark to light brown
Streak:Brownish white
Hardness (Mohs):4½
Hardness (Vickers):VHN100=310 - 330
Tenacity:Very brittle
Cleavage:Very Good
Perfect on {001}
Good on {100}
Density (measured):2.562 - 2.593 g/cm3
Density (calculated):2.71 g/cm3

Crystallography of Armstrongite

Crystal System:Monoclinic
Cell Parameters:a = 14.04Å, b = 14.16Å, c = 7.81Å
β = 109.55°
Ratio:a:b:c = 0.992 : 1 : 0.552
Unit Cell Volume:V 1,463.17 ų (Calculated from Unit Cell)
Z:4
Morphology:Crystals to 2cm, aggregates
Twinning:Polysynthetic, by rotation on [100]

Optical Data of Armstrongite

Type:Biaxial (-)
RI values: nα = 1.563 nβ = 1.569 nγ = 1.573
Maximum Birefringence:δ = 0.010

Chart shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:Low
Dispersion:strong r < v

Chemical Properties of Armstrongite

Formula:
CaZr[Si
 
6
O
 
15
]·3H
 
2
O
Essential elements:Ca, H, O, Si, Zr
All elements listed in formula:Ca, H, O, Si, Zr
Common Impurities:Ti,Al,Y,TR,Fe,Mg,Na,K

Relationship of Armstrongite to other Species

Related Minerals - Nickel-Strunz Grouping):

- +
9.EA.05Cuprorivaite
CaCu[Si
 
4
O
 
10
]
9.EA.05Gillespite
BaFe
2+
 
[Si
 
4
O
 
10
]
9.EA.05Effenbergerite
BaCu[Si
 
4
O
 
10
]
9.EA.05Wesselsite
SrCu[Si
 
4
O
 
10
]
9.EA.10Ekanite
(Ca,Fe
2+
 
,Pb)
 
2
(Th,U)[Si
 
8
O
 
20
]
9.EA.15Apophyllite-(KF)
KCa
 
4
[(F,OH)|Si
 
8
O
 
20
] · 8H
 
2
O
9.EA.15Apophyllite-(KOH)
KCa
 
4
[(OH,F)|Si
 
8
O
 
20
] · 8H
 
2
O
9.EA.15Apophyllite-(NaF)
NaCa
 
4
[F|Si
 
8
O
 
20
] · 8H
 
2
O
9.EA.20Magadiite
NaSi
 
7
O
 
13
(OH)
 
3
·3H
 
2
O
9.EA.25Dalyite
K
 
2
ZrSi
 
6
O
 
15
9.EA.25Davanite
K
 
2
TiSi
 
6
O
 
15
9.EA.30Sazhinite-(Ce)
Na
 
3
Ce[Si
 
6
O
 
15
] · 6H
 
2
O
9.EA.30Sazhinite-(La)
Na
 
3
La[Si
 
6
O
 
15
] · 2H
 
2
O
9.EA.40Okenite
CaSi
 
2
O
 
5
·2H
 
2
O
9.EA.45Nekoite
Ca
 
3
Si
 
6
O
 
15
·7H
 
2
O
9.EA.50Cavansite
Ca(VO)Si
 
4
O
 
10
·4H
 
2
O
9.EA.55Pentagonite
Ca(VO)Si
 
4
O
 
10
·4H
 
2
O
9.EA.60Penkvilksite
Na
 
4
Ti
 
2
Si
 
8
O
 
22
·4H
 
2
O
9.EA.60Tumchaite
Na
 
2
Zr(Si
 
4
O
 
11
)·2H
 
2
O
9.EA.65Nabesite
Na
 
2
BeSi
 
4
O
 
10
 * 4 H
 
2
O
9.EA.70Ajoite
(K,Na)Cu
 
7
[(OH)
 
6
|AlSi
 
9
O
 
24
] · 3H
 
2
O
9.EA.75Zeravshanite
Cs
 
4
Na
 
2
Zr
 
3
[Si
 
18
O
 
45
](H
 
2
O)
 
2
9.EA.80Bussyite-(Ce)
(Ce,REE)
 
3
(Na,H
 
2
O)
 
6
MnSi
 
9
Be
 
5
(O,OH)
 
30
F
 
4
9.EA.85Plumbophyllite
Pb
 
2
Si
 
4
O
 
10
·H
 
2
O
Related Minerals - Hey's Index Grouping:

- +
14.10.1Zircon
Zr[SiO
 
4
]
14.10.2Hafnon
(Hf,Zr)[SiO
 
4
]
14.10.3Zektzerite
LiNa(Zr,Ti,Hf)Si
 
6
O
 
15
14.10.4Parakeldyshite
Na
 
2
ZrSi
 
2
O
 
7
14.10.5Vlasovite
Na
 
2
ZrSi
 
4
O
 
11
14.10.6Keldyshite
(Na,H)
 
2
ZrSi
 
2
O
 
7
14.10.7Gaidonnayite
Na
 
2
Zr[Si
 
3
O
 
9
]·2H
 
2
O
14.10.8Terskite
Na
 
4
ZrSi
 
6
O
 
16
·2H
 
2
O
14.10.9Elpidite
Na
 
2
ZrSi
 
6
O
 
15
·3H
 
2
O
14.10.10Hilairite
Na
 
2
Zr[SiO
 
3
]
 
3
·3H
 
2
O
14.10.11Petarasite
Na
 
5
Zr
 
2
[(OH,Cl)|Si
 
6
O
 
18
]·2H
 
2
O
14.10.12Khibinskite
K
 
2
ZrSi
 
2
O
 
7
14.10.13Wadeite
K
 
2
Zr[Si
 
3
O
 
9
]
14.10.14Dalyite
K
 
2
ZrSi
 
6
O
 
15
14.10.15Kostylevite
K
 
2
ZrSi
 
3
O
 
9
·H
 
2
O
14.10.16Umbite
K
 
2
(Zr,Ti)Si
 
3
O
 
9
·H
 
2
O
14.10.17Paraumbite
K
 
3
Zr
 
2
H(Si
 
3
O
 
9
)
 
2
·nH
 
2
O
14.10.18Georgechaoite
NaKZr[Si
 
3
O
 
9
]·2H
 
2
O
14.10.19Gittinsite
CaZr[Si
 
2
O
 
7
]
14.10.20Calciocatapleiite
CaZrSi
 
3
O
 
9
·2H
 
2
O
14.10.21Calciohilairite
CaZr[SiO
 
3
]
 
3
·3H
 
2
O
14.10.23Lemoynite
(Na,K)
 
2
CaZr
 
2
Si
 
10
O
 
26
·5H
 
2
O
14.10.24Catapleiite
Na
 
2
Zr[Si
 
3
O
 
9
]·2H
 
2
O
14.10.25Baghdadite
Ca
 
3
(Zr,Ti)[O
 
2
|Si
 
2
O
 
7
]
14.10.26Lovozerite
Na
 
2
Ca(Zr,Ti)[Si
 
6
O
 
12
(OH,O)
 
6
]*H
 
2
O
14.10.27Låvenite
(Na,Ca)
 
2
(Mn
2+
 
,Fe
2+
 
)(Zr,Ti)[(O,OH,F)
 
2
|Si
 
2
O
 
7
]
14.10.28Penkvilksite
Na
 
4
Ti
 
2
Si
 
8
O
 
22
·4H
 
2
O
14.10.29Darapiosite
KNa
 
2
Li(Mn,Zn)
 
2
ZrSi
 
12
O
 
30
14.10.30Bazirite
BaZr[Si
 
3
O
 
9
]
14.10.31Komkovite
BaZr[Si
 
3
O
 
9
]·3H
 
2
O
14.10.32Zirsinalite
Na
 
6
(Ca,Mn
2+
 
,Fe
2+
 
)Zr[Si
 
6
O
 
18
]
14.10.33Tranquillityite
(Fe
2+
 
,Ca)
 
8
(Zr,Y)
 
2
Ti
 
3
[O
 
4
|SiO
 
4
]
 
3

Other Names for Armstrongite

Synonyms:
IMA1972-018
Other Languages:
German:Armstrongit
Russian:Армстронгит
Spanish:Armstrongita

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 Armstrongite

Reference List:American Mineralogist: 59: 208.

Soviet Physics – Crystallography: 23: 593.

Internet Links for Armstrongite

Search Engines:
  • Look for Armstrongite on Google
  • Look for Armstrongite images on Google
    • External Links:
  • Look for Armstrongite on Webmineral
  • Look for Armstrongite on Athena Mineralogy
  • Look for Armstrongite on Wikipedia
  • Look for Armstrongite on Mineralien Atlas
  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Search for Armstrongite in the Natural History Museum (London) online catalogue
  • Armstrongite details from Handbook of Mineralogy (PDF)
    • Mineral Dealers:
  • Wilensky Fine Minerals
  • Fine Minerals from Dan Weinrich Minerals
  • Buy Minerals and Crystals from Crystalarium.com
  • Mineral Classics - Worldwide Collector Quality Minerals and Gems
  • Search for - Armstrongite - on e-Rocks Mineral Sales & Auctions
  • High-end worldwide specimens & outstanding customer service
  • Top quality minerals from Kristalle of California
  • Buy minerals from Mineralium.com
  • Buy fine minerals and gemstones from Pala International
  • Find Armstrongite on www.crystalclassics.co.uk
  • Buy Fine Minerals from mineralsweb.com
  • Lapis Mineral Magazin
    • Jobs:
  • Mining & Geology Jobs

    • Page Sponsor

    Sponsorship:This page is currently not sponsored. Click here to sponsor this page.

    Localities for Armstrongite

    Hide Locality List
    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.
    (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
     
    • New South Wales
      • Lincoln Co.
        • Dubbo
    		http://www.alkane.com.au/projects/nsw/dubbo/DZP%20Summary%20Jan08.pdf
    Canada
     
    • Newfoundland and Labrador
      • Labrador
    		Powder Diffraction Jour. v.2 no.1, March1987
    Mongolia
     
    • Gobi Desert
    		Dokl.Akad. Nauk SSSR (1973) 209, 1185-1188
    Mineral and/or Locality
    Google
     
    www.mindat.org Web
    Copyright © Jolyon Ralph and Ida Chau 1993-2009. 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. If you would like to add information to improve the quality of our database, then click here to register. Current server date and time: 7th Nov 2009 11:47:37