Sheldrickite Mineral Data

General Sheldrickite Information

Chemical Formula:

NaCa3(CO3)2F3•(H2O)

Composition:

Molecular Weight = 338.25 gm

Sodium 6.80 % Na 9.16 % Na₂O

Calcium 35.55 % Ca 49.74 % CaO

Hydrogen 0.60 % H 5.33 % H₂O

Carbon 7.10 % C 26.02 % CO₂

Oxygen 33.11 % O

Fluorine 16.85 % F 16.85 % F

- % F -7.10 % -O=F₂

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

NaCa₃(CO₃)₂F₃•(H₂O)

Environment:

Found in a marble xenolith in the nepheline syenite intrusive unit close to a large unit of hornfels. A late stage hydrothermal infilling

IMA Status:

Approved IMA 1996 (Dana # Added)

Locality:

Poudrette quarry, Mont Saint-Hilaire, Rouville Co., Quebec, Canada. Link to MinDat.org Location Data.

Name Origin:

Named for George M. Sheldrick, creator of the SHELX software, widely used for the refinement of crystal structures.

Name Pronunciation:

Sheldrickite + Pronunciation

Synonym:

ICSD 76858

IMA1996-019

Sheldrickite Crystallography

Axial Ratios:

a:c = 1:2.24025

Cell Dimensions:

a = 6.718, c = 15.05, Z = 3; V = 588.23 Den(Calc)= 2.86

Crystal System:

Trigonal - Pyramidal H-M Symbol (3) Space Group: P 3₂

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

By Intensity(I/I_o): 2.01(1), 2.791(0.5), 2.508(0.4),

Physical Properties of Sheldrickite

Cleavage:

{001} Good

Color:

Colorless, White.

Density:

2.86

Diaphaneity:

Transparent to Translucent

Fracture:

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

Habit:

Aggregates - Made of numerous individual crystals or clusters.

Habit:

Blocky - Crystal shape tends to be equant (e.g. feldspars).

Hardness:

3 - Calcite

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Sheldrickite

Optical Data:

Uniaxial (+), w=1.538, e=1.563, bire=0.0250.

Calculated Properties of Sheldrickite

Electron Density:

Bulk Density (Electron Density)=2.84 gm/cc
note: Specific Gravity of Sheldrickite =2.86 gm/cc.

Fermion Index:

Fermion Index = 0.0014208854
Boson Index = 0.9985791146

Photoelectric:

PE_Sheldrickite= 4.67 barns/electron
U=PE_Sheldrickite x rElectron Density= 13.27 barns/cc.

Radioactivity:

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

Sheldrickite Classification

Dana Class:

16a.03.11.01 (16a)Carbonates - Hydroxyl or Halogen

(16a.03)where (A B)2 (XO3) Zq

(16a.03.11)Dana Group

16a.03.11.01 Sheldrickite! NaCa3(CO3)2F3•(H2O) P 3₂ 3

Strunz Class:

05.DC.15 05 - CARBONATES (NITRATES)

05.D - Carbonates with Additional Anions, with H2O

05.DC -With large cations

05.DC.15 Sheldrickite! NaCa3(CO3)2F3•(H2O) P 3₂ 3

Other Sheldrickite Information

References:

NAME( CanMin) PHYS. PROP.(Min.Mag.,Vol.61,p732,1997) OPTIC PROP.(Min.Mag.,Vol.61,p732,1997)

See Also:

Links to other databases for Sheldrickite :
1 - Alkali-Nuts(English)
2 - Alkali-Nuts(Francais)
3 - Am. Min. Crystal Structure Database
4 - Athena
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
15 - WWW-MINCRYST

Search for Sheldrickite using:

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

Visit our Advertisers for Sheldrickite :

Ask about Sheldrickite 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 Sheldrickite Specimen Label here :

Sheldrickite

NaCa3(CO3)2F3•(H2O)
Dana No: 16a.03.11.01 Strunz No: 05.DC.15
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.