Gatelite-(Ce) Mineral Data

[Newest Minerals] [Minerals for Sale] [Educational Articles] [About Us] [Image Gallery]
John Betts - Fine Minerals
Classic minerals, out-of-print books & magazines, plus informative articles for collectors

General Gatelite-(Ce) Information

Chemical Formula:

(Ca,Ce,La,Nd)4(Al,Mg,Fe)4[Si2O7][SiO4]3(O,F,OH)3

Composition:

Molecular Weight = 1,067.70 gm

Calcium 4.13 % Ca 5.78 % CaO

Lanthanum 6.50 % La 7.63 % La₂O₃

Cerium 18.37 % Ce 21.52 % Ce₂O₃

Praeseodymium 1.32 % Pr 1.54 % Pr₂O₃

Samarium 1.41 % Sm 1.63 % Sm₂O₃

Magnesium 1.14 % Mg 1.89 % MgO

Aluminum 7.83 % Al 14.80 % Al₂O₃

Iron 1.57 % Fe 2.02 % FeO

Silicon 13.42 % Si 28.70 % SiO₂

Hydrogen 0.15 % H 1.35 % H₂O

Neodymium 10.81 % Nd 12.61 % Nd₂O₃

Oxygen 32.82 % O

Fluorine 0.53 % F 0.53 % F

- % F -0.22 % -O=F₂

______ ______

100.00 % 99.78 % = TOTAL OXIDE

Empirical Formula:

Ca_1.1Ce_1.4La_0.5Nd_0.8Pr_0.1Sm_0.1Al_3.1Mg_0.5Fe²⁺_0.3Si_5.1O_20.3(OH)_1.6F_0.3

Environment:

Found as a late-stage mineral in the dolomitic levels of the Trimmouns Talc deposit intergrown with tornebohmite-(Ce). (related to epidote; structure)

IMA Status:

Approved IMA 2003 (Dana # Added)

Locality:

Trimouns talc deposit, Luzenac, Ariege, French Pyrenees, France. Link to MinDat.org Location Data.

Name Origin:

Named for Pierre Gatel, French mineral collector and founder of the Association Francaise de Micromineralogie.

Synonym:

IMA2001-050

Gatelite-(Ce) Image

Images:

Gatelite-(Ce)

Comments: B&W image of crystals of gatelite-(Ce). (AmMin, v88:223).
Location: Trimouns talc deposit, Luzenac, Ariege, French Pyrenees. Scale: Crystal Length 700 µm.
© R. Vernet / American Mineralogist

Gatelite-(Ce) Crystallography

Axial Ratios:

a:b:c =3.1445:1:3.0893

Cell Dimensions:

a = 17.77, b = 5.651, c = 17.458, Z = 4; beta = 116.18° V = 1,573.26 Den(Calc)= 4.51

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): 2.967(1)(215), 15.667(0.87)(001), 2.61(0.56)(612), 3.486(0.5)(412), 2.826(0.44)(020), 4.611(0.33)(210), 2.74(0.32)(015), 7.974(0.27)(200), 2.654(0.26)(403),

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

Bonazzi P , Bindi L , Parodi G C , American Mineralogist , 88 (2003) p.223-228, Gatelite-(Ce), a new REE-bearing mineral from Trimouns, French Pyrenees:, Crystal structure and polysomatic relationships with epidote and, tornebohmite-(Ce)

Physical Properties of Gatelite-(Ce)

Cleavage:

{100} Good, {001} Imperfect

Color:

Colorless.

Diaphaneity:

Transparent

Fracture:

Brittle - Irregular - Very brittle fracture producing irregular fragments

Habit:

Bladed - Aggregates of thin lath-like crystals (e.g. kyanite).

Habit:

Euhedral Crystals - Occurs as well-formed crystals showing good external form.

Habit:

Striated - Parallel lines on crystal surface or cleavage face.

Hardness:

6-7 - Orthoclase-Quartz

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Gatelite-(Ce)

Optical Data:

Biaxial (?)

NCalc= 1.81 - from Gladstone-Dale relationship (KC = 0.1787) where Ncalc=Dcalc*KC+1

Calculated Properties of Gatelite-(Ce)

Electron Density:

Bulk Density (Electron Density)=4.20 gm/cc
note: Specific Gravity of Gatelite-(Ce) =4.51 gm/cc.

Fermion Index:

Fermion Index = 0.03
Boson Index = 0.97

Photoelectric:

PE_{Gatelite-(Ce)}= 199.82 barns/electron
U=PE_{Gatelite-(Ce)} x r_electron= 838.62 barns/cc.

Radioactivity:

GRapi = 38,208.99 (Gamma Ray American Petroleum Institute Units)
Concentration of Gatelite-(Ce) per GRapi unit = 26.17 (PPM)

Gatelite-(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) 796.06 ±199.02 grams of pure Gatelite-(Ce) .

**Estimated Radioactivity from Gatelite-(Ce)** - weak
Specimen Size Weight/Volume (Sphere) *	Calculated Activity Bequerols (Bq)	Calculated Activity Curies (Ci)	Estimated Activity GR(api)	Estimated Exposure (mRem**)/hr If Held in Hand For One Hour
1000 gm / 7.51 cm	862,231	2.33E-05	38,208.99	12.56
100 gm / 3.49 cm	86,223	2.33E-06	3,820.90	1.26
10 gm / 1.62 cm	8,622	2.33E-07	382.09	0.13
1 gm / 7.51 mm	862	2.33E-08	38.21	0.01
0.1 gm / 3.49 mm	86	2.33E-09	3.82	0.00
0.01 gm / 1.62 mm	9	2.33E-10	0.38	0.00
0.001 gm / 0.75 mm	1	2.33E-11	0.04	0.00

Weight of pure Gatelite-(Ce) in grams (gm) and Calculated Diameter of a Sphere with a Density of 4.51 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 ( 1.92 % Th) From Sum REE Elements (38.41 % REE)

Gatelite-(Ce) Classification

Dana Class:

58.02.01a.08 (58)Sorosilicate Insular, Mixed, Single, and Larger Tetrahedral Groups

(58.02)with cations in [6] and higher coordination; single and double groups (n=1,2)

(58.02.01a)Epidote group (Clinozoisite subgroup)

58.02.01a.01 Clinozoisite! Ca2Al3(SiO4)3(OH)=Ca2AlAl2(SiO4)(Si2O7)O(OH) P 2₁/m 2/m

58.02.01a.02 Epidote! Ca2(Fe,Al)3(SiO4)3(OH)=Ca2(Fe,Al)Al2(SiO4)(Si2O7)O(OH) P 2₁/m 2/m

58.02.01a.03 Epidote-(Pb)! (Ca,Pb,Sr)2(Al,Fe)3(SiO4)(Si2O7)O(OH) P 2₁/m 2/m

58.02.01a.04 Mukhinite Ca2Al2V(SiO4)3(OH) P 2₁/m 2/m

58.02.01a.05 Piemontite Ca2(Al,Mn,Fe)3(SiO4)3(OH)=Ca2(Mn,Fe)Al2(SiO4)(Si2O7)O(OH) P 2₁/m 2/m

58.02.01a.06 Piemontite-(Sr)! (Ca,Mn)(Sr,Ca)Mn(Al,Mn,Fe)2(SiO4)(Si2O7)O(OH) P 2₁/m 2/m

58.02.01a.07 Manganipiemontite-(Sr)! CaSr(Mn,Fe)2Al[Si3O12](OH) P 2₁/m 2/m

58.02.01a.08 Gatelite-(Ce)! (Ca,Ce,La,Nd)4(Al,Mg,Fe)4[Si2O7][SiO4]3(O,F,OH)3 P 2₁/a 2/m

58.02.01a.09 Clinozoisite-(Sr)! CaSrAl3(Si2O7)(SiO4)O(OH) P 2₁/m 2/m

58.02.01a.10 Uedaite-(Ce)! MnCeAl2Fe(Si2O7)(SiO4)O(OH) P 2₁/m 2/m

58.02.01a.11 Epidote-(Sr)! CaSrAl2Fe(Si2O7)(SiO4)O(OH) P 2₁/m 2/m

Strunz Class:

09.BG.50 09 - SILICATES (Germanates)

09.B - Sorosilicates

09.BG -Sorosilicates with mixed SiO4 and Si2O7 groups;

09.BG.50 Gatelite-(Ce)! (Ca,Ce,La,Nd)4(Al,Mg,Fe)4[Si2O7][SiO4]3(O,F,OH)3 P 2₁/a 2/m

Other Gatelite-(Ce) Information

References:

NAME( AmMin, Vol 88, p 223) PHYS. PROP.(AmMin, Vol 88, p 223)

See Also:

Links to other databases for Gatelite-(Ce) :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - Google Images
4 - Google Scholar
5 - MinDAT
6 - MinMax(Deutsch)
7 - MinMax(English)
8 - Mineralienatlas (Deutsch)
9 - QUT Mineral Atlas
10 - Ruff.Info

Search for Gatelite-(Ce) using:

[ALTAVISTA] [AOL] [All-The-Web] [HotBot] [Ixquick] [MAMMA] [MSN.COM] [Netscape] [Scirus] [Teoma] [Wikipedia] [YAHOO]

Visit our Advertisers for Gatelite-(Ce) :

AA Mineral Specimens

B & L Fine Minerals

Crystalarium.com

Dan Weinrich Fine Minerals

Dan Weinrich Auctions

Dakota Matrix

Desert Winds Gems and Minerals

John Betts Fine Minerals

Mason's Minerals

Mineral News

Mineral of the Month Club

Wrights Rock Shop

Translate Gatelite-(Ce) Mineral Data :

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

Gatelite-(Ce)

(Ca,Ce,La,Nd)4(Al,Mg,Fe)4[Si2O7][SiO4]3(O,F,OH)3
Dana No: 58.02.01a.08 Strunz No: 09.BG.50
Locality:

Notes: