Downeyite Mineral Data

General Downeyite Information

Chemical Formula:

SeO2

Composition:

Molecular Weight = 110.96 gm

Selenium 71.16 % Se 100.00 % SeO₂

Oxygen 28.84 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

SeO₂

Environment:

Sublimation product of gases escaping through vents in actively burning culm banks in anthracite coal deposits; forms at about 200 deg C near the vents.

IMA Status:

Approved IMA 1977

Locality:

Glen Lyon, Luzerne Co.,Pennsylvania, USA Link to MinDat.org Location Data.

Name Origin:

Named for Wayne F. Downey, Jr., of Harrisburg, Pennsylvania, USA, who first collected the mineral.

Name Pronunciation:

Downeyite + Pronunciation

Synonym:

ICSD 72366

PDF 22-1314

Downeyite Crystallography

Axial Ratios:

a:c = 1:0.60645

Cell Dimensions:

a = 8.36, c = 5.07, Z = 8; V = 354.34 Den(Calc)= 4.16

Crystal System:

Tetragonal - Ditetragonal Dipyramidal H-M Symbol (4/m 2/m 2/m) Space Group: P 4/mbc

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

By Intensity(I/I_o): 3.36(1), 4.64(0.85), 5.28(0.75),

Physical Properties of Downeyite

Color:

Colorless.

Density:

4.146

Diaphaneity:

Transparent

Luster:

Adamantine

Streak:

white

Optical Properties of Downeyite

Optical Data:

NCalc= 1.81 - from Gladstone-Dale relationship (KC = 0.195) where Ncalc=Dcalc*KC+1
NCalc= 1.81 - from Gladstone-Dale relationship (KC = 0.195) where Ncalc=Dmeas*KC+1

Calculated Properties of Downeyite

Electron Density:

Bulk Density (Electron Density)=3.75 gm/cc
note: Specific Gravity of Downeyite =4.16 gm/cc.

Fermion Index:

Fermion Index = 0.05
Boson Index = 0.95

Photoelectric:

PE_Downeyite= 55.58 barns/electron
U=PE_Downeyite x rElectron Density= 208.36 barns/cc.

Radioactivity:

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

Downeyite Classification

Dana Class:

04.04.03.01 (04)Simple Oxides

(04.04)with a cation charge of 4+ (A++++ O2)

(04.04.03)Dana Group

04.04.03.01 Downeyite SeO2 P 4/mbc 4/m 2/m 2/m

04.04.03.02 Paratellurite TeO2 P 4₁2₁2,P 4₃2₁2 4 2 2

Strunz Class:

04.DE.05 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate

04.D - Metal:Oxygen = 1:2 and similar

04.DE -With medium-sized cations; with various polyhedra

04.DE.05 Downeyite SeO2 P 4/mbc 4/m 2/m 2/m

Other Downeyite Information

References:

NAME( AntBidBlaNic3) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

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

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Print or Cut-and-Paste your Downeyite Specimen Label here :

Downeyite

SeO2
Dana No: 04.04.03.01 Strunz No: 04.DE.05
Locality:

Notes:

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