Dittmarite Mineral Data

General Dittmarite Information

Chemical Formula:

(NH4)Mg(PO4)•(H2O)

Composition:

Molecular Weight = 155.33 gm

Magnesium 15.65 % Mg 25.95 % MgO

Phosphorus 19.94 % P 45.69 % P₂O₅

Hydrogen 2.60 % H - % Calc as (NH₄)₂O

Hydrogen 1.30 % H 11.60 % H₂O

Nitrogen 9.02 % N 16.76 % (NH₄)₂O

Oxygen 51.50 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

(NH₄)Mg(PO₄)•(H₂O)

Environment:

Found in dryer parts of bat guano in caves.

IMA Status:

Valid Species (Pre-IMA) 1887

Locality:

Skipton lava tube caves, 40 km southwest of Ballarat, Victoria, Australia. Link to MinDat.org Location Data.

Name Origin:

Named for William Dittmar (1833-1892), Professor of Chemistry, University of Glasgow, Glasgow, Scotland.

Name Pronunciation:

Dittmarite + Pronunciation

Dittmarite Image

Images:

Dittmarite Newberyite

Comments: Translucent crystalline dittmaritewith more opaque newberyite.
Location: Skipton Caves, Victoria, Australia. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Dittmarite Crystallography

Axial Ratios:

a:b:c =0.6401:1:0.5467

Cell Dimensions:

a = 5.606, b = 8.758, c = 4.788, Z = 2; V = 235.08 Den(Calc)= 2.19

Crystal System:

Orthorhombic - Pyramidal H-M Symbol (mm2) Space Group: P mn2₁

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

By Intensity(I/I_o): 8.77(1), 2.8(0.5), 2.92(0.4),

Physical Properties of Dittmarite

Cleavage:

{???} Perfect

Color:

Colorless.

Density:

2.19

Diaphaneity:

Transparent

Hardness:

5 - Apatite

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Dittmarite

Gladstone-Dale:

CI meas= -0.469 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.469 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2571,KPDmeas= 0.2571,KC= 0.1749
Ncalc = 1.38

Optical Data:

Biaxial (-), a=1.549, b=1.569, g=1.571, bire=0.0220, 2V(Calc)=34, 2V(Meas)=40.

Calculated Properties of Dittmarite

Electron Density:

Bulk Density (Electron Density)=2.26 gm/cc
note: Specific Gravity of Dittmarite =2.19 gm/cc.

Fermion Index:

Fermion Index = 0.1
Boson Index = 0.9

Photoelectric:

PE_Dittmarite= 1.34 barns/electron
U=PE_Dittmarite x rElectron Density= 3.02 barns/cc.

Radioactivity:

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

Dittmarite Classification

Dana Class:

40.01.02.01 (40)Hydrated Phosphates, etc

(40.01)where A++ B++ (XO4) ï¿½ x(H2O)

(40.01.02)Dana Group

40.01.02.01 Dittmarite (NH4)Mg(PO4)•(H2O) P mn2₁ mm2

40.01.02.02 Niahite (NH4)(Mn,Mg,Ca)PO4•(H2O) P mn2₁ mm2

Strunz Class:

08.CH.20 08 - PHOSPHATES, ARSENATES, VANADATES

08.C - Phosphates without Additional Anions, with H2O

08.CH -With large and medium-sized cations, RO4:H2O < 1:1

08.CH.20 Dittmarite (NH4)Mg(PO4)•(H2O) P mn2₁ mm2

08.CH.20 Niahite (NH4)(Mn,Mg,Ca)PO4•(H2O) P mn2₁ mm2

Other Dittmarite Information

References:

NAME( AntBidBlaNic4) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Dittmarite :
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

Search for Dittmarite using:

[AOL] [Bing] [Dog Pile] [GeoScienceWorld] [HotBot] [Ixquick] [Lycos] [MAMMA] [Scirus] [Teoma] [WebCrawler] [Wikipedia] [YAHOO]

Visit our Advertisers for Dittmarite :

Ask about Dittmarite here :
Ask-A-Mineralogist from the Mineralogical Society of America
Mindat.org's Discussion Groups
Original Rockhounds Discussion Group
Rockhounds Discussion Group on Yahoo Groups
Mineral Discussion Forum from Fabre Minerals - also available in Español

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

Dittmarite

(NH4)Mg(PO4)•(H2O)
Dana No: 40.01.02.01 Strunz No: 08.CH.20
Locality:

Notes:

Dakota Matrix
Excalibur Minerals
Exceptional Minerals
Hudson Insitute
John Betts Fine Minerals
Mc Dougall Minerals
Mineral News
Rock and Mineral Shows
Weinrich Minerals, Inc.