Gregoryite Mineral Data

Gregoryite Mineral Data +

[New Updates] [Gallery 1] [Gallery 2] [Gallery 3] [Rock Shop Gallery]
Serving the mineral collector and educator community since 1970
Over 900,000 mineral specimens in stock
New minerals acquired weekly - Wright's Rock Shop

General Gregoryite Information

Chemical Formula:

(Na2,K2,Ca)CO3

Composition:

Molecular Weight = 115.06 gm

Potassium 20.39 % K 24.56 % K₂O

Sodium 23.98 % Na 32.32 % Na₂O

Calcium 3.48 % Ca 4.87 % CaO

Carbon 10.44 % C 38.25 % CO₂

Oxygen 41.71 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

0.6(Na₂)0.3(K₂)Ca_0.1(CO₃)

IMA Status:

Approved IMA 1981

Locality:

Link to MinDat.org Location Data.

Gregoryite Image

Images:

Gregoryite Nyerereite

Comments: Sodium (nyereteite) and potassium (gregoryite) carbonates, not stable in normal atmosphere, collected molten from the volcano and maintained in inert argon atmosphere.
Location: Ol Doinyo Lengai Vulkan, Maasai Steppe, East Africa Rift Valley, Tanzania. See Link. Scale: Rock size 2 cm.
© Richard Dale / Dale Minerals

Gregoryite Crystallography

Axial Ratios:

a:c = 1:1.26251

Cell Dimensions:

a = 5.215, c = 6.584, Z = 2; V = 155.07 Den(Calc)= 2.46

Crystal System:

Hexagonal - Dihexagonal PyramidalH-M Symbol (6mm) Space Group: P 6₃mc

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

By Intensity(I/I_o): 2.66(1), 2.61(0.75), 3.29(0.4),

Physical Properties of Gregoryite

Color:

White.

Density:

2.27

Streak:

white

Optical Properties of Gregoryite

Optical Data:

NCalc= 1.49 - from Gladstone-Dale relationship (KC = 0.2005) where Ncalc=Dcalc*KC+1
NCalc= 1.46 - from Gladstone-Dale relationship (KC = 0.2005) where Ncalc=Dmeas*KC+1

Calculated Properties of Gregoryite

Electron Density:

r_electron=2.42 gm/cc
note: r_Gregoryite=2.46 gm/cc.

Fermion Index

Fermion Index = 0.00141
Boson Index = 0.99859

Photoelectric:

PE_Gregoryite= 2.98 barns/electron
U=PE_Gregoryite x r_electron= 7.21 barns/cc.

Radioactivity:

GRapi = 289.43 (Gamma Ray American Petroleum Institute Units)

Estimated Radioactivity from Gregoryite - barely detectable

Gregoryite Classification

Dana Class:

14.1.2.2 (14)Anhydrous Carbonates

(14.1)with Simple Formula A+ CO3

(14.1.2)Dana Group

14.1.2.1 Vaterite CaCO3 P 6₃/mmc 6/m 2/m 2/m

14.1.2.2 Gregoryite (Na2,K2,Ca)CO3 P 6₃mc 6mm

Strunz Class:

V/B.05-40 V - Nitrates, Carbonates and Borates

V/B - Waterfree carbonates [CO3]2- without unfamiliar anions

V/B.05 - Eitelie - Shortite - Carbocernaite series

V/B.05-10 Eitelite Na2Mg(CO3)2 R 3 3

V/B.05-20 Nyerereite Na2Ca(CO3)2 C mc2₁ mm2

V/B.05-30 Natrofairchildite Na2Ca(CO3)2 P 6₃/mmc 6/m 2/m 2/m

V/B.05-40 Gregoryite (Na2,K2,Ca)CO3 P 6₃mc 6mm

V/B.05-50 Fairchildite K2Ca(CO3)2 P 6₃/mmc 6/m 2/m 2/m

V/B.05-55 Zemkorite (Na,K)2Ca(CO3)2 P 6₃/mmc, P 6₃mc, P 6₂c- Hex

V/B.05-60 Butschliite K2Ca(CO3)2 R 3m 3 2/m

V/B.05-70 Shortite Na2Ca2(CO3)3 Amm2 mm2

V/B.05-80 Sahamalite-(Ce) (Mg,Fe)Ce2(CO3)4 P 2₁/a 2/m

V/B.05-90 Remondite-(Ce) Na3(Ce,La,Ca,Na,Sr)3(CO3)5 P 2₁ 2

V/B.05-92 Remondite-(La)! Na3(La,Ce,Ca)3(CO3)5 P 2₁ 2

V/B.05-95 Petersenite-(Ce) (Na,Ca)4(Ce,La,Nd)2(CO3)5 P 2₁ 2

V/B.05-98 Calcioburbankite Na3(Ca,REE,Sr)3(CO3)5 P 6₃mc 6mm

V/B.05-100 Burbankite (Na,Ca)3(Sr,Ba,Ce)3(CO3)5 P 6₃/mmc 6/m 2/m 2/m

V/B.05-110 Khanneshite (NaCa)3(Ba,Sr,Ce,Ca)3(CO3)5 P 6₃mc 6mm

V/B.05-120 Carbocernaite (Ca,Na)(Sr,Ce,Ba)(CO3)2 P mc2₁ mm2

Other Gregoryite Information

References:

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

See Also:

Links to other databases for Gregoryite :
1 -Am. Min. Crystal Structure Database 2 -Athena 3 - EUROmin Project 4 -Google Images 5 -Google Scholar 6 -Handbook of Mineralogy (UofA) 7 -MinDAT 8 -MinMax(Deutsch) 9 -MinMax(English) 10 -Mineralienatlas (Deutsch) 11 -QUT Mineral Atlas 12 -École des Mines de Paris

Search for Gregoryite using:

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

Visit our Advertisers for Gregoryite :
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 Gregoryite Mineral Data :

Ask about Gregoryite 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 Gregoryite Specimen Label here :

Gregoryite

(Na2,K2,Ca)CO3
Dana No: 14.1.2.2 Strunz No: V/B.05-40
Locality:

Notes: