Sahamalite-(Ce) Mineral Data

Advertisment

Dakota Matrix was founded in 1996 and has offered systematic and rare mineral specimens online since 1998.

Exceptional Minerals features excellent, high quality mineral specimens for sale. We also have a weekly Best Offer Mineral Auction.

John Betts - Fine Minerals, New York. Dealers of Fine Minerals and Natural Crystal Clusters since 1989. We buy rock collections, we buy gem collections, we buy mineral collections.

Weinrich Minerals, A Dealer in Fine Mineral Specimens - Since 1989. We buy collections and single high quality specimens.

General Sahamalite-(Ce) Information

Chemical Formula:

(Mg,Fe++)Ce2(CO3)4

Composition:

Molecular Weight = 552.46 gm

Cerium 50.72 % Ce 59.41 % Ce₂O₃

Magnesium 3.30 % Mg 5.47 % MgO

Iron 2.53 % Fe 3.25 % FeO

Carbon 8.70 % C 31.86 % CO₂

Oxygen 34.75 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Mg_0.75Fe²⁺_0.25Ce₂(CO₃)₄

Environment:

Accessory mineral in a rare-earth-bearing barite-dolomite carbonatite.

IMA Status:

Valid Species (Pre-IMA) 1953

Locality:

Sulfide Queen mine, Mountain Pass, San Bernardino Co., California, USA. Link to MinDat.org Location Data.

Name Origin:

Named for Thure Georg Sahama (1910-1983), Finnish geochemist and petrologist, University of Helsinki, Helsinki, Finland.

Name Pronunciation:

Sahamalite-(Ce) + Pronunciation

Synonym:

ICSD 31271

PDF 6-189

Sahamalite-(Ce) Image

Images:

Sahamalite-(Ce)

Comments: White granular aggregate of sahamalite-(Ce) on matrix.
Location: Silfide Queen Deposit, Mountain Pass Mine, San Bernandino Co., California, USA. Scale: Specimen Size 9x7x5 mm.
© Sergey Vasiliev / Systematic Mineralogy

Sahamalite-(Ce) Crystallography

Axial Ratios:

a:b:c =1.0357:1:0.2856

Cell Dimensions:

a = 16.79, b = 16.21, c = 4.63, Z = 6; beta = 106.7° V = 1,206.98 Den(Calc)= 4.56

Crystal System:

Monoclinic - PrismaticH-M Symbol (2/m) Space Group: P 2₁/a

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

By Intensity(I/I_o): 2.87(1), 3.65(1), 3.9(1),

Crystal Structure:

Mouse
drag1 - LMB Manipulate Structure
drag2 - RMB Resize/Rotate
Keyboard
S - Stereo Pair on/off
H - Help Screen
I - Data Info
A - Atoms On/Off
P - Polyhedra On/Off
B - Bonds On/Off
Help on Above

Pertlik F , Preisinger A , Tschermaks Mineralogische und Petrographische Mitteilungen , 31 (1983) p.39-46, Crystal structure of sahamalite (Mg,Fe)RE2(CO3)4, Locality: Mountain Pass mine, San Bernardino County, California

Physical Properties of Sahamalite-(Ce)

Cleavage:

{010} Indistinct

Color:

Colorless.

Density:

4.3

Diaphaneity:

Transparent

Streak:

white

Optical Properties of Sahamalite-(Ce)

Gladstone-Dale:

CI meas= -0.032 (Excellent) - where the CI = (1-KPDmeas/KC)
CI calc= 0.026 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1654,KPDmeas= 0.1753,KC= 0.1698
Ncalc = 1.73 - 1.77

Optical Data:

Biaxial (-), a=1.679, b=1.776, g=1.807, bire=0.1280, 2V(Calc)=56, 2V(Meas)=57.

Calculated Properties of Sahamalite-(Ce)

Electron Density:

Bulk Density (Electron Density)=4.15 gm/cc
note: Specific Gravity of Sahamalite-(Ce) =4.56 gm/cc.

Fermion Index:

Fermion Index = 0.0049587627
Boson Index = 0.9950412373

Photoelectric:

PE_{Sahamalite-(Ce)}= 258.21 barns/electron
U=PE_{Sahamalite-(Ce)} x r_electron=1,072.05 barns/cc.

Radioactivity:

GRapi = 49,262.21 (Gamma Ray American Petroleum Institute Units)
Concentration of Sahamalite-(Ce) per GRapi unit = 20.30 (PPM)

Sahamalite-(Ce) is Radioactive as defined in 49 CFR 173.403. Greater than 70 Bq / gram.

Estimated Maximum U.S. Postal Shipping Size (10 mRem/hr limit, Unshielded 10 cm box) 617.44 ±154.36 grams of pure Sahamalite-(Ce) .

**Estimated Radioactivity from Sahamalite-(Ce)** - weak
Specimen Size Weight/Volume (Sphere) *	Calculated Activity Becquerels (Bq)	Calculated Activity Curies (Ci)	Estimated Activity GR(api)	Estimated Exposure (mRem**)/hr If Held in Hand For One Hour
1000 gm / 7.48 cm	1,136,224	3.07E-05	49,262.21	16.20
100 gm / 3.47 cm	113,622	3.07E-06	4,926.22	1.62
10 gm / 1.61 cm	11,362	3.07E-07	492.62	0.16
1 gm / 7.48 mm	1,136	3.07E-08	49.26	0.02
0.1 gm / 3.47 mm	114	3.07E-09	4.93	0.00
0.01 gm / 1.61 mm	11	3.07E-10	0.49	0.00
0.001 gm / 0.75 mm	1	3.07E-11	0.05	0.00

Weight of pure Sahamalite-(Ce) in grams (gm) and Calculated Diameter of a Sphere with a Density of 4.56 gm/cc.*
Goverment Estimate of Average Annual Exposure ( 360 mRem) **
Note: 10 microsieverts/hr = 1 mRem/hr **
Max Permissable Adult Dose 50,000 mRem/yr (hands), 15,000 mRem/yr (eyes)
Lethal Dose LD(50) Exposure 400,000 to 500,000 mRem
Estimated Thorium Activity ( 2.54 % Th) From Sum REE Elements (50.72 % REE)

Sahamalite-(Ce) Classification

Dana Class:

14.04.02.01 (14)Anhydrous Carbonates

(14.04)with Compound Formula A+2 B++2 (CO3)4

(14.04.02)Dana Group

14.04.02.01 Sahamalite-(Ce) (Mg,Fe)Ce2(CO3)4 P 2₁/a 2/m

14.04.02.02 Paratooite-(La)! REE3(Ca,Sr)2NaCu(CO3)8 P 222 or P 222₁ 2 2 2

Strunz Class:

05.AD.05 05 - CARBONATES (NITRATES)

05.A - Carbonates without additional anions, without H2O

05.AD -With rare-earth elements (REE)

05.AD.05 Sahamalite-(Ce) (Mg,Fe)Ce2(CO3)4 P 2₁/a 2/m

Other Sahamalite-(Ce) Information

References:

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

See Also:

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

Search for Sahamalite-(Ce) using:

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

Visit our Advertisers for Sahamalite-(Ce) :

Cape Minerals Google Search for Sahamalite-(Ce)
Dakota Matrix Minerals Google Search for Sahamalite-(Ce)
Excalibur Mineral Corp. Google Search for Sahamalite-(Ce)
Exceptional Minerals Google Search for Sahamalite-(Ce)
John Betts Fine Minerals Search for Sahamalite-(Ce)
McDougall Minerals Google Search for Sahamalite-(Ce)
Mineral News Website Link
Rock and Mineral Shows Google Search for Sahamalite-(Ce)
Weinrich Minerals, Inc. Google Search for Sahamalite-(Ce)

Ask about Sahamalite-(Ce) 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 Sahamalite-(Ce) Specimen Label here :

Sahamalite-(Ce)

(Mg,Fe++)Ce2(CO3)4
Dana No: 14.04.02.01 Strunz No: 05.AD.05
Locality:

Notes: