Swaknoite Mineral Data

General Swaknoite Information

Chemical Formula:

(NH4)2Ca(HPO4)2•(H2O)

Composition:

Molecular Weight = 286.13 gm

Calcium 14.01 % Ca 19.60 % CaO

Phosphorus 21.65 % P 49.61 % P₂O₅

Hydrogen 2.82 % H - % Calc as (NH₄)₂O

Hydrogen 1.41 % H 12.59 % H₂O

Nitrogen 9.79 % N 18.20 % (NH₄)₂O

Oxygen 50.33 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

(NH₄)₂•(H₂O)Ca(HPO₄)₂

Environment:

Dolomite walls of the Arnhem cave.

IMA Status:

Approved IMA 1991

Locality:

Windhoek, Namibia. Link to MinDat.org Location Data.

Name Origin:

Named for the acronym for the Siud Wes Aftica Karst Navorsing Organisasie (SWANKNO), a speleological association in Namibia.

Name Pronunciation:

Swaknoite + Pronunciation

Synonym:

IMA1991-021

Swaknoite Crystallography

Axial Ratios:

a:b:c =2.8311:1:0.875

Cell Dimensions:

a = 20.959, b = 7.403, c = 6.478, Z = 4; V = 1,005.12 Den(Calc)= 1.89

Crystal System:

Orthorhombic Space Group: Unk

$Help on X Ray Diffraction:$ X Ray Diffraction:

By Intensity(I/I_o): 6.99(1), 3.705(0.89), 10.5(0.57),

Physical Properties of Swaknoite

Color:

White.

Density:

1.91

Diaphaneity:

Transparent

Fracture:

Brittle - Generally displayed by glasses and most non-metallic minerals.

Habit:

Acicular - Occurs as needle-like crystals.

Habit:

Rosette - Bundled tabular aggregates resembling rose flower petals.

Hardness:

1.5-2 - Talc-Gypsum

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Swaknoite

Gladstone-Dale:

CI meas= -0.526 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.542 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2695,KPDmeas= 0.2667,KC= 0.1748
Ncalc = 1.33

Optical Data:

Biaxial (+), a=1.506, b=1.51, g=1.512, bire=0.0060, 2V(Calc)=70, 2V(Meas)=65-70.

Calculated Properties of Swaknoite

Electron Density:

Bulk Density (Electron Density)=1.98 gm/cc
note: Specific Gravity of Swaknoite =1.91 gm/cc.

Fermion Index:

Fermion Index = 0.09
Boson Index = 0.91

Photoelectric:

PE_Swaknoite= 2.74 barns/electron
U=PE_Swaknoite x rElectron Density= 5.42 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Swaknoite is Not Radioactive

Swaknoite Classification

Dana Class:

39.03.04.01 (39)Hydrated Acid Phosphates, etc

(39.03)with miscellaneous formulae

(39.03.04)Dana Group

39.03.04.01 Swaknoite (NH4)2Ca(HPO4)2•(H2O) Unk Ortho

Strunz Class:

08.CJ.10 08 - PHOSPHATES, ARSENATES, VANADATES

08.C - Phosphates without Additional Anions, with H2O

08.CJ -With only large cations

08.CJ.10 Mundrabillaite (NH4)2Ca(HPO4)2•(H2O) Pm,P 2,P 2/m Mono

08.CJ.10 Swaknoite (NH4)2Ca(HPO4)2•(H2O) Unk Ortho

Other Swaknoite Information

References:

NAME( Dana8) PHYS. PROP.(Am.Min.,Vol.78,p1110,1993) OPTIC PROP.(Am.Min.,Vol.78,p1110,1993)

See Also:

Links to other databases for Swaknoite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - Ecole des Mines de Paris
5 - GeoScienceWorld
6 - Google Images
7 - Google Scholar
8 - Handbook of Mineralogy (MinSocAm)
9 - Handbook of Mineralogy (UofA)
10 - MinDAT
11 - Mineralienatlas (Deutsch)
12 - Online Mineral Museum
13 - QUT Mineral Atlas
14 - Ruff.Info

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Print or Cut-and-Paste your Swaknoite Specimen Label here :

Swaknoite

(NH4)2Ca(HPO4)2•(H2O)
Dana No: 39.03.04.01 Strunz No: 08.CJ.10
Locality:

Notes:

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