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Ramsdellite R050552



Name: Ramsdellite
RRUFF ID: R050552
Ideal Chemistry: MnO2
Locality: Lake Valley, Sierra County, New Mexico, USA
Source: Dave Bunk Minerals
Owner: RRUFF
Description: Black bladed crystals
Status: The identification of this mineral is confirmed by single-crystal X-ray diffraction and chemical analysis.
Mineral Group: [ Ramsdellite (2) ]
CHEMISTRY 
RRUFF ID: R050552.2
Sample Description: Microprobe fragment
Measured Chemistry: (Mn4+0.98Al0.02)Σ=1(O1.98(OH)0.02)Σ=2
RAMAN SPECTRUM 
RRUFF ID:
Sample Description: Unoriented sample
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Direction of polarization of laser relative to fiducial mark:
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BROAD SCAN WITH SPECTRAL ARTIFACTS
RRUFF ID: R050552
Wavelength:
Sample Description: Unoriented sample
Instrument settings: Thermo Almega XR 532nm @ 100% of 150mW
INFRARED SPECTRUM (Attenuated Total Reflectance) 
RRUFF ID: R050552.1
Instrument settings: SensIR Durascope on a Nicolet Magna 860 FTIR
Resolution:
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POWDER DIFFRACTION 
RRUFF ID: R050552.1
Sample Description: Powder, cell parameters are from single crystal
Cell Refinement Output: a: 9.26(2)Å    b: 2.840(5)Å    c: 4.557(9)Å
alpha: 90°    beta: 90°    gamma: 90°   Volume: 119.8(3)Å3    Crystal System: orthorhombic
  File Type Information Close
Output file from the Bruker D8 Advance instrument. Includes device headers and XY data.

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REFERENCES for Ramsdellite

American Mineralogist Crystal Structure Database Record: [view record]

Anthony J W, Bideaux R A, Bladh K W, and Nichols M C (1990) Handbook of Mineralogy, Mineral Data Publishing, Tucson Arizona, USA, by permission of the Mineralogical Society of America. [view file]

Ramsdell L S (1932) An X-ray study of psilomelane and wad, American Mineralogist, 17, 143-149   [view file]

Fleischer M, Richmond W E (1943) The manganese oxide minerals: a preliminary report, Economic Geology, 38, 269-286   [view file]

Fleischer M (1943) New mineral names, American Mineralogist, 28, 615-615   [view file]

Fleischer M, Richmond W E, Evans H T (1962) Studies of the manganese oxides. V. Ramsdellite, MnO2, an orthorhombic dimorph of pyrolusite, American Mineralogist, 47, 47-58   [view file]

Majmundar H H (1969) Ramsdellite and groutite from Nova Scotia, The Canadian Mineralogist, 9, 718-720   [view file]

Potter R M, Rossman G R (1979) The tetravalent manganese oxides: identification, hydration, and structural relationships by infrared spectroscopy, American Mineralogist, 64, 1199-1218   [view file]

Kohler T, Armbruster T, Libowitzky E (1997) Hydrogen bonding and Jahn-Teller distortion in groutite, α-MnOOH, and manganite, γ-MnOOH, and their relations to the manganese dioxides ramsdellite and pyrolusite, Journal of Solid State Chemistry, 133, 486-500

Post J E, Heaney P J (2004) Neutron and synchrotron X-ray diffraction study of the structures and dehydration behaviors of ramsdellite and "groutellite", American Mineralogist, 89, 969-975   [view file]

Post J E, McKeown D A, Heaney, P J (2020) Raman spectroscopy study of manganese oxides: Tunnel structures, American Mineralogist, 105, 1175-1190   [view file]