Pahasapaite Mineral Data

[Content and History] [Recent Issues] [Back Issues] [Subscriptions] [Contacts]
See Also: [Diamond Crystals] [Excalibur Minerals] [Hudson Institute] [Minerals on CDROM]
Mineral News was founded some twenty years ago and has developed a following of
avid mineral collectors seeking timely information about new finds and other items
of interest to the collector community. Articles are solicited from collector and scientific authors.

General Pahasapaite Information

Chemical Formula:

Li8(Ca,Li,K,Na)11Be24(PO4)24•38(H2O)

Composition:

Molecular Weight = 3,532.65 gm

Potassium 1.33 % K 1.60 % K₂O

Sodium 0.13 % Na 0.18 % Na₂O

Lithium 2.28 % Li 4.91 % Li₂O

Calcium 6.24 % Ca 8.73 % CaO

Beryllium 6.12 % Be 16.99 % BeO

Phosphorus 21.04 % P 48.22 % P₂O₅

Hydrogen 2.17 % H 19.38 % H₂O

Oxygen 60.69 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Li₈Ca_5.5Li_3.6K_1.2Na_0.2Be₂₄(PO₄)₂₄•38(H₂O)

Environment:

late-stage mineral in seams in fractured beryl crystals in a complex granite pegmatite.

IMA Status:

Approved IMA 1987

Locality:

Tip Top mine, 8.5 km southwest of Custer, Custer County, South Dakota, USA. Link to MinDat.org Location Data.

Name Origin:

From Pahasapa, the Lakota Sioux word for Black Hills, South Dakota, USA.

Name Pronunciation:

Pahasapaite + Pronunciation

Synonym:

ICSD 71430

PDF 41-1384

Pahasapaite Image

Images:

Pahasapaite

Comments: Lilac colored pahasapaite in matrix.
Location: Tip Top Mine, Fourmile, Custer District, Custer Co., South Dakota, USA. Scale: Picture size 3.5 mm.
© Thomas Witzke / Abraxas-Verlag

Pahasapaite Crystallography

Cell Dimensions:

a = 13.781, Z = 1; V = 2,617.23 Den(Calc)= 2.24

Crystal System:

Isometric - TetartoidalH-M Symbol (2 3) Space Group: I 23

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

By Intensity(I/I_o): 9.6(1), 3.248(0.9), 3.684(0.9),

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

Rouse R C , Peacor D R , Merlino S , American Mineralogist , 74 (1989) p.1195-1202, Crystal structure of pahasapaite, a beryllophosphate mineral with a distorted, zeolite rho framework

Physical Properties of Pahasapaite

Cleavage:

None

Color:

Colorless, Yellow green, Light pink.

Density:

2.28

Diaphaneity:

Transparent

Fracture:

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

Hardness:

4.5 - Between Fluorite and Apatite

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Pahasapaite

Gladstone-Dale:

CI meas= 0.01 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= -0.007 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2335,KPDmeas= 0.2294,KC= 0.2318
Ncalc = 1.52 - 1.53

Optical Data:

Isotropic, n=1.523.

Calculated Properties of Pahasapaite

Electron Density:

Bulk Density (Electron Density)=2.25 gm/cc
note: Specific Gravity of Pahasapaite =2.24 gm/cc.

Fermion Index:

Fermion Index = 0.06
Boson Index = 0.94

Photoelectric:

PE_Pahasapaite= 2.02 barns/electron
U=PE_Pahasapaite x r_electron= 4.54 barns/cc.

Radioactivity:

GRapi = 19.22 (Gamma Ray American Petroleum Institute Units)
Concentration of Pahasapaite per GRapi unit = 5.20 (%)

Estimated Radioactivity from Pahasapaite - barely detectable

Pahasapaite Classification

Dana Class:

40.05.07.01 (40)Hydrated Phosphates, etc

(40.05)with miscellaneous formulae

(40.05.07)Dana Group

40.05.07.01 Pahasapaite Li8(Ca,Li,K,Na)11Be24(PO4)24•38(H2O) I 23 2 3

Strunz Class:

08.CA.25 08 - PHOSPHATES, ARSENATES, VANADATES

08.C - Phosphates without Additional Anions, with H2O

08.CA -With small and large/medium cations

08.CA.25 Pahasapaite Li8(Ca,Li,K,Na)11Be24(PO4)24•38(H2O) I 23 2 3

Other Pahasapaite 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 Pahasapaite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - Ecole des Mines de Paris
5 - Google Images
6 - Google Scholar
7 - Handbook of Mineralogy (MinSocAm)
8 - Handbook of Mineralogy (UofA)
9 - MinDAT
10 - MinMax(Deutsch)
11 - MinMax(English)
12 - Mineralienatlas (Deutsch)
13 - QUT Mineral Atlas
14 - Ruff.Info
15 - WWW-MINCRYST

Search for Pahasapaite using:

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

Visit our Advertisers for Pahasapaite :

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 Pahasapaite Mineral Data :

Ask about Pahasapaite 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 Pahasapaite Specimen Label here :

Pahasapaite

Li8(Ca,Li,K,Na)11Be24(PO4)24•38(H2O)
Dana No: 40.05.07.01 Strunz No: 08.CA.25
Locality:

Notes: