Mineralogy Database

Ramsdellite Mineral Data

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General Ramsdellite Information

Help on Chemical  Formula: Chemical Formula: MnO2
Help on Composition: Composition: Molecular Weight = 86.94 gm
   Manganese  63.19 %  Mn  100.00 % MnO2
   Oxygen     36.81 %  O
             ______        ______ 
             100.00 %      100.00 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: Mn4+O2
Help on Environment: Environment: Manganese deposits with pyrolusite.
Help on IMA Status: IMA Status: Valid Species (Pre-IMA) 1943
Help on Locality: Locality: Lake Valley, Sierra County, New Mexico. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named after the American mineralogist, Lewis S. Ramsdell (1895-1975), of the University of Michigan, who first described the mineral.
Help on Name Pronunciation: Name Pronunciation: Ramsdellite + Pronunciation Say RAMSDELLITE
Help on Synonym: Synonym: Groutellite - pseudomorph of ramsdellite after groutite
  ICSD 78331
  PDF 44-142

Ramsdellite Image

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Comments: Large mass of radiating ramsdellite crystals with terminated crystals.
Location: Lake Valley District, Sierra Co., New Mexico, USA. Scale: 11x10x8 cm.
© John Betts - Fine Minerals

Ramsdellite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =0.4889:1:0.3091
Help on Cell Dimensions: Cell Dimensions: a = 4.533, b = 9.27, c = 2.866, Z = 4; V = 120.43 Den(Calc)= 4.79
Help on Crystal System: Crystal System: Orthorhombic - Dipyramidal H-M Symbol (2/m 2/m 2/m) Space Group: Pbnm
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 4.06(1), 2.32(0.65), 2.55(0.6),

Physical Properties of Ramsdellite

Help on Cleavage: Cleavage: {???} Good
Help on Color: Color: Iron black, Black, Steel gray.
Help on Density: Density: 4.37
Help on Diaphaneity: Diaphaneity: Opaque
Help on Fracture: Fracture: Brittle - Generally displayed by glasses and most non-metallic minerals.
Help on Habit: Habit: Granular - Generally occurs as anhedral to subhedral crystals in matrix.
Help on Habit: Habit: Massive - Fibrous - Distinctly fibrous fine-grained forms.
Help on Habit: Habit: Platy - Sheet forms (e.g. micas).
Help on Hardness: Hardness: 3 - Calcite
Help on Luster: Luster: Metallic
Help on Streak: Streak: brownish black

Optical Properties of Ramsdellite

Help on Optical Data: Optical Data: NCalc= 2.89 - from Gladstone-Dale relationship (KC = 0.394) where Ncalc=Dcalc*KC+1
NCalc= 2.72 - from Gladstone-Dale relationship (KC = 0.394) where Ncalc=Dmeas*KC+1

Calculated Properties of Ramsdellite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=4.52 gm/cc
note: Specific Gravity of Ramsdellite =4.79 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.0001766733
Boson Index = 0.9998233267
Help on Photoelectric: Photoelectric: PERamsdellite = 16.61 barns/electron
U=PERamsdellite x rElectron Density= 75.02 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Ramsdellite is Not Radioactive

Ramsdellite Classification

Help on  Dana Class: Dana Class: (04)Simple Oxides
  (04.04)with a cation charge of 4+ (A++++ O2)
  (04.04.07)Dana Group Ramsdellite MnO2 Pbnm 2/m 2/m 2/m
Help on  Strunz Class: Strunz Class: 04.DB.15a 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate
  04.D - Metal:Oxygen = 1:2 and similar
  04.DB -With medium-sized cations; chains of edge-sharing octahedra
04.DB.15a Paramontroseite VO2 Pbnm 2/m 2/m 2/m
04.DB.15a Ramsdellite MnO2 Pbnm 2/m 2/m 2/m

Other Ramsdellite Information

Help on References: References: NAME( MinRec) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990)
Help on See Also: See Also: Links to other databases for Ramsdellite :
1 - Am. Min. Crystal Structure Database
2 - Amethyst Galleries' Mineral Gallery
3 - Athena
4 - EUROmin Project
5 - Ecole des Mines de Paris
6 - GeoScienceWorld
7 - Glendale Community College
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
19 - YupRocks

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Dana No: Strunz No: 04.DB.15a





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