Prosopite Mineral Data

Prosopite Mineral Data +

[Register] [Auction Rules] [Current Listing] [About Us] [Site Map]
e-Rocks.com, auction and sales venue for all rock and mineral enthusiasts
Our mission is to provide an online centre for Buyers and Sellers with reliable service and support
Brought to you by Thames Valley Minerals

General Prosopite Information

Chemical Formula:

CaAL2(F,OH)8

Composition:

Molecular Weight = 242.05 gm

Calcium 16.56 % Ca 23.17 % CaO

Aluminum 22.29 % Al 42.12 % Al₂O₃

Hydrogen 0.83 % H 7.44 % H₂O

Oxygen 13.22 % O

Fluorine 47.09 % F 47.09 % F

- % F -19.83 % -O=F₂

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

CaAl₂F₆(OH)₂

IMA Status:

Valid Species (Pre-IMA) 1853

Locality:

St. Peter's Dome near Pike's Peak, Colorado, USA. Link to MinDat.org Location Data.

Name Origin:

From the Greek prosopon - "mask."

Synonym:

ICSD 10267

PDF 5-307

Prosopite Image

Images:

Prosopite

Comments: Pale violet prosopite microcrystals.
Location: Ivigtut, Greenland. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Prosopite Crystallography

Axial Ratios:

a:b:c =0.6588:1:0.6021

Cell Dimensions:

a = 7.32, b = 11.11, c = 6.69, Z = 4; beta = 95° V = 542.00 Den(Calc)= 2.97

Crystal System:

Monoclinic - PrismaticH-M Symbol (2/m) Space Group: A2/a

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

By Intensity(I/I_o): 4.35(1), 1.837(0.6), 2.13(0.6),

Forms:

Mouse
Dbl Clk - Start-Stop Rotation
RMB - Cycle Display Modes
Drag1 - Manipulate Crystal
Drag2 - Resize
Keyboard
S - Stereo
I - Indicies
<space> - Start-Stop Rotation
F - Fit to Screen
M - Menu
Help on Above

Forms: [ 0 1 0] [ 1 1 1] [ 1 1 1] [ 1 1 0]

Warning: this large pop-up is very compute intensive and may not work well with some computers.

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

Pudovkina Z V , Chernitsova N M , Pyatenko Y A , Journal of Structural Chemistry , 14 (1973) p.345-347, Refinement of the crystalline structure of prosopite, CaAl2F4(OH)4

Physical Properties of Prosopite

Cleavage:

[111] Perfect, [111] Perfect, [111] Perfect

Color:

White, Greenish white, Reddish white.

Density:

2.88 - 2.89, Average = 2.88

Diaphaniety:

Transparent

Fracture:

Uneven - Flat surfaces (not cleavage) fractured in an uneven pattern.

Habit:

Crystalline - Fine - Occurs as well-formed fine sized crystals.

Habit:

Massive - Granular - Common texture observed in granite and other igneous rock.

Hardness:

4-5 - Fluorite-Apatite

Luminescence:

None.

Luster:

Vitreous - Dull

Magnetism:

Nonmagnetic

Streak:

white

Optical Properties of Prosopite

Gladstone-Dale:

CI meas= 0.046 (Good) - where the CI = (1-KPDmeas/KC)
CI calc= 0.073 (Fair) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1699,KPDmeas= 0.1749,KC= 0.1833

Optical Data:

Biaxial (+), a=1.501, b=1.503, g=1.51, bire=0.0090, 2V(Calc)=58, 2V(Meas)=62.75. Dispersion none.

Pleochroism (x):

colorless.

Pleochroism (y):

colorless.

Pleochroism (z):

colorless.

Calculated Properties of Prosopite

Electron Density:

r_electron=2.81 gm/cc
note: r_Prosopite=2.89 gm/cc.

Fermion Index

Fermion Index = 0.00028
Boson Index = 0.99972

Photoelectric:

PE_Prosopite= 2.98 barns/electron
U=PE_Prosopite x r_electron= 8.39 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)

Prosopite is Not Radioactive

Prosopite Classification

Dana Class:

11.6.9.1 (11)Halide Complexes; Alumino-fluorides

(11.6)with miscellaneous formulae

(11.6.9)Dana Group

11.6.9.1 Prosopite CaAL2(F,OH)8 A2/a 2/m

Strunz Class:

III/C.03-10 III - Halogenides

III/C - Double halogenides with water, Fluorides

III/C.03 - Prosopite - Boldyrevite series

III/C.03-10 Prosopite CaAL2(F,OH)8 A2/a 2/m

III/C.03-20 Chiolite Na5Al3F14 P 4/mnc 4/m 2/m 2/m

III/C.03-30 Weberite Na2MgAlF7 I mma 2/m 2/m 2/m

III/C.03-40 Usovite Ba2CaMgAl2F14 C 2/c or Cc Mono

III/C.03-45 Karasugite SrCaAl(F,OH)7 P 2₁/c 2/m

III/C.03-50 Carlhintzeite Ca2AlF7·(H2O) C1,C1 Tri

III/C.03-55 Rosenbergite AlF3·3(H2O) P 4/n 4/m

III/C.03-60 Ralstonite NaxMgxAl2-x(F,OH)6·(H2O) F d3m 4/m 3 2/m

III/C.03-70 Neighborite NaMgF3 Pcmn 2/m 2/m 2/m

III/C.03-80 Boldyrevite* NaCaMgAl3F14·4(H2O) None

Other Prosopite Information

References:

NAME( Duda&Rejl90) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Ford32)

Search for Prosopite using:

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

Visit our Advertisers for Prosopite :
AA Mineral Specimens
B and L Minerals
Dan Weinrich Fine Minerals
Dan Weinrich Auctions
e-Rocks Auctions
Excalibur Minerals
Exceptional Minerals
Fabre Minerals
Greenside Minerals
John Betts Fine Minerals
Masons Minerals
Minernet.it
Mineral News
Mineral of the Month Club
MineralsWeb Fine Minerals
Rockshop.cz Kalat Fine Minerals
T G Fine Minerals
Wrights Rock Shop

Translate Prosopite Mineral Data :

Ask about Prosopite 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 Prosopite Specimen Label here :

Prosopite

CaAL2(F,OH)8
Dana No: 11.6.9.1 Strunz No: III/C.03-10
Locality:

Notes: