Senaite Mineral Data

General Senaite Information

Chemical Formula:

Pb(Ti,Fe,Mn)21O38

Composition:

Molecular Weight = 1,904.66 gm

Titanium 25.14 % Ti 41.94 % TiO₂

Manganese 11.54 % Mn 14.90 % MnO

Iron 20.52 % Fe 26.40 % FeO

Lead 10.88 % Pb 11.72 % PbO

Oxygen 31.92 % O

______ ______

100.00 % 94.96 % = TOTAL OXIDE

Empirical Formula:

PbTi₁₀Fe²⁺₇Mn²⁺₄O₃₈

IMA Status:

Valid Species (Pre-IMA) 1898

Locality:

Dattos, Curralinho, and other localities near Diamantina, Minas Gerias, Brazil. Link to MinDat.org Location Data.

Name Origin:

Named for Joaquim de Costa Sena, Esola de Minas, Ouro Preto, Brazil.

Name Pronunciation:

Senaite

Synonym:

ICSD 84

PDF 20-1048

Senaite Image

Images:

Senaite

Comments: Brownish-black senaite cleavage.
Location: Dattas, near Diamantina, Minas Gerais, Brazil. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Images:

Senaite

Comments: Black crystal of senaite.
Location: Presidente Kibitschek, Minas Gerias, Brazil. Scale: Crystal size 2 mm.
© Dave Barthelmy

Senaite Crystallography

Axial Ratios:

a:c = 1:2.0024

Cell Dimensions:

a = 10.393, c = 20.811, Z = 3; V = 1,946.73 Den(Calc)= 4.87

Crystal System:

Trigonal - Rhombohedral H-M Symbol ( 3) Space Group: R 3

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

By Intensity(I/I_o): 2.894(1), 3.43(0.9), 1.981(0.75),

Physical Properties of Senaite

Cleavage:

None

Color:

Black.

Density:

5.3

Diaphaneity:

Subopaque to Opaque

Fracture:

Conchoidal - Fractures developed in brittle materials characterized by smoothly curving surfaces, (e.g. quartz).

Habit:

Rhombohedral Crystals - Occurs as well-formed crystals showing rhobohedral crystals.

Habit:

Tabular - Form dimensions are thin in one direction.

Hardness:

6-6.5 - Orthoclase-Pyrite

Luster:

Sub Metallic

Streak:

brownish black

Optical Properties of Senaite

Gladstone-Dale:

CI meas= -0.091 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.187 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.308,KPDmeas= 0.283,KC= 0.2594
Ncalc = 2.26 - 2.37

Optical Data:

Uniaxial (-), e=2.5.

Calculated Properties of Senaite

Electron Density:

Bulk Density (Electron Density)=4.94 gm/cc
note: Specific Gravity of Senaite =5.30 gm/cc.

Fermion Index:

Fermion Index = 0.06
Boson Index = 0.94

Photoelectric:

PE_Senaite= 192.85 barns/electron
U=PE_Senaite x rElectron Density= 953.07 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Senaite is Not Radioactive

Senaite Classification

Dana Class:

08.05.01.04 (08)Multiple Oxides with Nb, Ta, and Ti

(08.05)Dana Type

(08.05.01)Crichtonite group (ABC18 T2 O38)

08.05.01.01 Landauite NaMnZn2(Ti,Fe)6Ti12O38 R 3 3

08.05.01.02 Loveringite (Ca,Ce)(Ti,Fe,Cr,Mg)21O38 R 3 3

08.05.01.03 Crichtonite (Sr,La,Ce,Y)(Ti,Fe,Mn)21O38 R 3 3

08.05.01.04 Senaite Pb(Ti,Fe,Mn)21O38 R 3 3

08.05.01.05 Davidite-(La) (La,Ce,Ca)(Y,U)(Ti,Fe)20O38 R 3 3

08.05.01.06 Davidite-(Ce) (Ce,La)(Y,U)(Ti,Fe)20O38 R 3 3

08.05.01.07 Mathiasite (K,Ca,Sr)(Ti,Cr,Fe,Mg)21O38 R 3 3

08.05.01.08 Lindsleyite (Ba,Sr)(Ti,Cr,Fe,Mg)21O38 R 3 3

08.05.01.09 Dessauite! (Sr,Pb)(Y,U)(Ti,Fe)20O38 P 3 3

08.05.01.10 Cleusonite! Pb(U,U)(Ti,Fe,Fe)20(O,OH)38 R 3 3

08.05.01.11 Gramaccioliite-(Y)! (Pb,Sr)(Y,Mn)Fe2(Ti,Fe)18O38 R 3 3

Strunz Class:

04.CC.40 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate

04.C - Metal:Oxygen = 2:3, 3:5, and Similar

04.CC -With large and medium-sized cations

04.CC.40 Crichtonite (Sr,La,Ce,Y)(Ti,Fe,Mn)21O38 R 3 3

04.CC.40 Dessauite! (Sr,Pb)(Y,U)(Ti,Fe)20O38 P 3 3

04.CC.40 Davidite-(Ce) (Ce,La)(Y,U)(Ti,Fe)20O38 R 3 3

04.CC.40 Davidite-(La) (La,Ce,Ca)(Y,U)(Ti,Fe)20O38 R 3 3

04.CC.40 Mathiasite (K,Ca,Sr)(Ti,Cr,Fe,Mg)21O38 R 3 3

04.CC.40 Lindsleyite (Ba,Sr)(Ti,Cr,Fe,Mg)21O38 R 3 3

04.CC.40 Landauite NaMnZn2(Ti,Fe)6Ti12O38 R 3 3

04.CC.40 Loveringite (Ca,Ce)(Ti,Fe,Cr,Mg)21O38 R 3 3

04.CC.40 Senaite Pb(Ti,Fe,Mn)21O38 R 3 3

04.CC.40 Cleusonite! Pb(U,U)(Ti,Fe,Fe)20(O,OH)38 R 3 3

04.CC.40 Gramaccioliite-(Y)! (Pb,Sr)(Y,Mn)Fe2(Ti,Fe)18O38 R 3 3

Other Senaite Information

References:

NAME( Dana8) PHYS. PROP.(Dana8) OPTIC PROP.(Dana8)

See Also:

Links to other databases for Senaite :
1 - Alkali-Nuts(English)
2 - Alkali-Nuts(Francais)
3 - Am. Min. Crystal Structure Database
4 - Athena
5 - EUROmin Project
6 - Ecole des Mines de Paris
7 - GeoScienceWorld
8 - Google Images
9 - Google Scholar
10 - Handbook of Mineralogy (MinSocAm)
11 - Handbook of Mineralogy (UofA)
12 - HyperPhysics
13 - MinDAT
14 - Mineralienatlas (Deutsch)
15 - Online Mineral Museum
16 - QUT Mineral Atlas
17 - Ruff.Info
18 - WWW-MINCRYST

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Senaite

Pb(Ti,Fe,Mn)21O38
Dana No: 08.05.01.04 Strunz No: 04.CC.40
Locality:

Notes:

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