| |
Previous
and present work
REASONS FOR OPTICAL
ANISOTROPY IN CUBIC ORE MINERALS
Since the beginning of this
century ore microscopists were interested in the anomalous, optically
anisotropic behavior of cubic ore minerals like pyrite, cuprite,
and minerals of the spinel group. The unusual effect was attributed
to the influence of tectonic stress, anomalous solid solutions
series, incorporation of trace elements (As in pyrite, Zn in
spinels), and influence of rough preparation methods.
During the study of approximately
500 ore mineral sections (ore microscopy, XRD, SEM) the following
reasons for the anomalous anisotropy were revealed:
(1) The mineral donathite (discredited)
is a spinel of the chromite-magnetite (ferrite) ss-series which
exhibits tiny exsolution lamellae. Because the lamellae are sub-micron
sized, because they are parallel to each other, and because they
have two different sets of optical constants (one relating to
magnetite, the other one to chromite), they show the effect of
form birefringence. Etched samples reveal the sub-micron sized
lamellae with a SEM.
(2) A similar phenomenon is
found in extremely fine-zoned magnetites of skarn deposits. The
parallel zones of sub-micron thickness and changing composition
lead also to the phenomenon of form birefringence. Etching of
the polished samples with HCl makes the fine zones also visible
in the SEM.
(3) A careful examination of
hundreds of pyrite, spinel, and cuprite sections which had been
polished with diamond pastes, showed that they were optically
anisotropic without exception. (The very strong anisotropy in
cuprite had been used over decades as a determinative feature!)
An investigation of the polished surfaces with the electron channeling
pattern (ECP) technique on a SEM proved that the upper, polished
surface layers were destroyed. The application of alkaline silica
solutions in the final polishing process (a chemo-mechanical
method) lead to optically isotropic sections and to undistorted
surface layers in the ECPs. Examination of differently oriented
polished sections revealed that the surface deformation by mechanical
(diamond) polishing methods is related to the surface symmetry
of the sections.
Related
papers:
Libowitzky E (1991) Donathite:
An intergrowth of magnetite and chromite, causing form birefringence.
N Jb Miner Mh 10, 449-456
Libowitzky E (1993) Ursachen
optischer Anisotropieeffekte in kubischen Erzmineralen. Berichte
der DMG 1, 1993 (Add Vol Eur J Mineral 5), M-P-10,79, 246, abstract
Libowitzky E (1994) Anisotropic
pyrite: A polishing effect. Phys Chem Minerals, 21, 97 - 103
Libowitzky E (1994) Optical
anisotropy of cuprite caused by polishing. Can Mineral, 32, 353
- 358
Libowitzky E (1994) Optical
anisotropy in the spinel group: A polishing effect. Eur J Mineral,
6, 187 -194
Libowitzky E (1994) Optical
anisotropy of zoned magnetites due to form birefringence. Mineral
Petrol, 52, 107 - 111
Burns PC, Hawthorne FC, Libowitzky
E, Bordes N, Ewing RC (1997) Donathite discredited: A mixture
of two spinels. N Jb Mineral Mh, 1997, 163-174
Libowitzky
E (2001) The pseudo-biabsorption of trigonal rock-forming carbonates.
N Jb Miner Mh, 2001, 67 - 79
HYDROUS SPECIES IN MINERALS
Hydrogen, as a major
or trace constituent of minerals, has considerable influence
on the physical properties of rocks and minerals (deformation
behavior, rheology, conductivity). Hydrogen occurs usually in
the form of OH groups or water molecules in minerals. If H containing
minerals are stable to high temperatures and pressures, they
may provide an important source of hydrogen in the Earth's interior.
Hence, trace amounts of water in minerals like olivine, perovskite,
pyroxenes, and garnets, as well as the behavior of the stoichiometric
OH and water groups in the high-pressure mineral lawsonite are
of interest. In addition, the features of hydrous species in
oxide and silicate structures is important for technically applied
materials like the microporous zeolites, precursors of ceramics,
and proton conductors.
IR spectroscopy provides
one of the most sensitive methods in determining hydrogen in
minerals. Using polarized radiation and oriented crystal sections
the orientation of O-H vectors in the structure can be determined,
and even quantitative information can be obtained by accurate
measurements and calibration procedures. Additional information
on the behavior of OH and water molecules (if present in larger
amounts) can be gained from other spectroscopic techniques (e.g.
proton-NMR) and from X-ray and neutron diffraction.
(1) FTIR investigations
of pure Mg-olivine (forsterite) revealed that trace amounts of
hydrogen are incorporated in the form of OH defects which are
related to Si vacancies. The polarized IR spectra show several
sharp bands between 3500 and 3700 cm-1 which indicate
different OH vector directions (predominantly II x) and additional
trace elements in the coordination sphere of the OH groups.
(2) A similar mechanism
was observed in CaTiO3 perovskite. The FTIR spectrum
shows only two bands in the OH stretching region (around 3300
cm-1) which are indicative for OH incorporation in
connection with a vacant Ca site. The stretching frequencies
are in good agreement with a distorted environment around the
vacancy. The type of OH defect is very similar to that of high-pressure
MgSiO3 perovskite.
The room-temperature structure
of lawsonite -
The arrow indicates the hopping motion (dynamic disorder)
of the water molecule |
(3) Single-crystal X-ray diffraction
of lawsonite, CaAl2[Si2O7](OH)2.H 2O, revealed
low-temperature phase transitions from space group Cmcm (at room-temperature)
to Pmcn (between 273 and 150 K), and finally P21cn
(below 150 K). The transitions are characterized by the apparent
rotation of both hydroxide and water groups, thus lowering the
symmetry in two steps. The apparent rotations are accompanied
by the formation of a cooperative H bond system.
The phase transitions were
monitored by distinct X-ray reflections. They cause also nonlinearities
in lattice parameters and optical constants.
An FTIR spectroscopic investigation
of oriented lawsonite slabs resulted in a good correlation between
band positions, H bond lengths, and OH vector directions at low
temperatures. However, the smooth change of the spectra, the
strong shift of absorption bands, and the unstable position of
the water molecule between two proton acceptors, indicate rather
a dynamic order-disorder transition than a displacive phase transition.
These results are also confirmed by preliminary proton NMR and
neutron diffraction studies.
The lawsonite-type mineral
hennomartinite shows similar phase transitions at elevated temperatures.
However, multiple disorder and twinning, as well as a monoclinic
distortion at room-temperature (after a tempering process) draw
a more complicated picture.

The water molecule and hydroxide
groups in the channel of the hemimorphite structure |
(4) Knowledge about lawsonite
and about features of dynamic proton order-disorder and related
phase transitions led also to the discovery of proton disorder
and a phase transition at 98 K in hemimorphite, Zn4[Si2O7](OH)2 · H2O. IR
bands showed also a smooth development and strong band shifts
with changing temperature. In addition, more bands than expected
were observed in the polarized spectra. In a neutron study, the
hydroxide proton revealed smeared anisotropic displacement parameters,
and the environment of this H atom showed also two possible proton
acceptors. A Time-of-Flight neutron single-crystal diffraction
study at low temperatures revealed that the low-temperature phase
is characterized by a superstructure with doubled b and c lattice
parameters. Thus, freezing of the dynamically disordered H atoms
leads to an ordered H atom arrangement along the ordered structural
channels in hemimorphite. The ordered proton positions are in
agreement with the obtained IR spectra.

Structures of MnOOH: Manganite
and groutite |
(5) Polarized IR spectroscopic
investigations of single-crystals of MeOOH (Me = Al, Fe, Mn)
minerals showed similar spectra of all substances, the O-H stretching
energies, however, are different and in good agreement with the
respective hydrogen bond lengths. In addition, the in-plane and
out-of-plane bending modes were observed. Peculiar absorption
features in the spectra between the stretching mode and the bending
modes were assigned to the anharmonicity-resonance enhanced overtones
of the bending modes. Increasing anharmonicity leads to increased
intensity of the mentioned band(s) and is related with decreasing
hydrogen bond lengths.
|

The broad OH absorption band
in the IR spectrum of serandite
|
(6) Polarized infrared (IR)
absorption spectra of oriented single-crystal slabs of mozartite CaMn3+O[SiO3(OH)], pectolite NaCa2[Si3O8(OH)], serandite NaMn2[Si3O8(OH)], and
members of the natrochalcite series (Na1-xKx)Cu2(H3O 2)[SO4]2 (x
= 0, 0.5, 1), which contain very strong hydrogen bonds
due to very short O···O distances (2.44
- 2.50 Å), show broad absorption bands parallel to the
respective O-H vector directions in the structures. These bands
which start below 3500 cm-1 show their approximate
maxima between 1000 to 1500 cm-1, which is in agreement
with literature data on very strong H bonds. They interfere with
sharp absorption bands of silicate and sulfate vibrations, and
typically show "transmission windows" which are well
known from spectra of organic materials with comparably short
H bonds.
|

IR calibration line based on
stoichiometric mineral hydrates and hydroxides
|
(7) IR spectroscopy
is a useful tool also for the quantitative characterization of
hydrous species in minerals. If proper experimental conditions
are followed (polarized spectra of oriented or orthogonal crystal
sections in cases of anisotropic crystals; knowledge about polarizer
extinction ratios), the Beer-Lambert law (A = ·c ·t),
which relates absorbance (A), concentration (c),
and thickness (t) by the molar absorption coefficient
( ), may be used for the determination
of water in geological materials. The molar absorption coefficient,
however, can only be determined by calibration on standard materials
with known water concentration. Experiments with different stoichiometric
mineral hydrates and hydroxides confirmed that only the integrated
absorbance Ai (band area) can be used among
different materials. Further, a direct correlation between absorbance
and water concentration fails, because the absorption coefficient
is strongly dependent on hydrogen bond strengths. Hence, the
resulting calibration line is expressed in relation to band energies
( ) by: i [cm-2 per
mol H2O / L] = 246.6 · (3753 - [cm-1]), regression
coefficient r2 0.98.
(8) The frequency of
an O-H stretching vibration is a valuable measure for the strength
of a hydrogen bond. It is correlated to H bond lengths, i.e.
O-H, O···O and H···O
distances: The high-energy end is represented by very weak H
bonds with d(O···O) 3.0 Å and at
3500 - 3700 cm-1, the low-energy end is found at very
strong H bonds with d(O···O) even
below 2.5 Å and bands at 700 - 1500 cm-1. Whereas
previous d - correlation
diagrams were limited either by insufficient number of data or
by restricted data range, a recent d - correlation
in minerals uses 125 d(O···O)- and
47 d(H···O)- data
pairs from silicates, oxi-hydroxides, sulphates, etc. containing
OH, H2O or H3O2 units with wavenumbers
between 1000 and 3700 cm-1. A correlation function
is established in the form =
3592 - 304·109 · exp(-d(O···O) /
0.1321), R2 = 0.96. Scatter of data is mainly caused
by deviation from straight H bonds (avoided if d(H···O) data
are used) and cationic effects.

Correlation of O-H stretching
frequency and d(O···O) in
minerals |
Related papers:
Armbruster
T, Libowitzky E, Diamond L, Auernhammer M, Bauerhansl P, Hoffmann
C, Irran E, Kurka A, Rosenstingl H (1994) Crystal chemistry and
optics of bazzite from Furkabasistunnel (Switzerland). Mineral
Petrol, 52, 113 - 126
Libowitzky
E, Beran A (1994) OH-Defekte in Forsterit. Mitt Österr Miner
Ges, 139, 331 - 333. Abstract.
Libowitzky
E, Beran A (1995) OH-defects in forsterite. Phys Chem Minerals,
22, 387 - 392
Libowitzky
E, Armbruster T (1995) Low-temperature phase transitions and
the role of hydrogen bonds in lawsonite. Am Mineral, 80, 1277
- 1285
Libowitzky
E, Armbruster A (1996) Lawsonite-type phase transitions in hennomartinite, SrMn2[Si2O7](OH)2·H 2O. Am
Mineral, 81, 9 - 18
Beran
A, Libowitzky E, Armbruster T (1996) A single-crystal infrared
spectroscopic and X-ray investigation of an untwinned San Benito
perovskite. Can Mineral, 34, 803 - 809
Libowitzky
E, Rossman GR (1996) Principles of quantitative absorbance measurements
in anisotropic crystals. Phys Chem Minerals, 23, 319 - 327
Libowitzky
E, Rossman GR (1996) FTIR spectroscopy of lawsonite between 82
and 325 K. Am Mineral, 81, 1080 - 1091
Kozlova
SG, Gabuda SP, Armbruster T, Libowitzky E (1996) Hydrogen atom
localization in lawsonite using single-crystal PMR data. IUCR-1996
abstract
Libowitzky,
E (1996) Order-disorder phase transitions in lawsonite and hemimorphite.
Mitt ÖMG, 141, 132 - 133, abstract
Libowitzky,
E (1996) Single-crystal IR spectroscopy of MeO(OH) minerals (Me
= Al, Fe, Mn). Mitt ÖMG, 141, 134 - 135, abstract
Libowitzky
E (1996) Proton disorder, phase transitions, and IR spectroscopy
in minerals. EMSM, Kiev, abstract
Beran
A, Libowitzky E (1996) OH-groups in natural perovskite - An IR
spectroscopic study. Phase Transitions, 58, 211 - 215
Nyfeler
D, Hoffmann C, Armbruster T, Kunz M, Libowitzky E (1996) Orthorhombic
Jahn-Teller distortion and Si-OH in mozartite CaMn3+O[SiO3OH], due
to topological stress: A structure modeling, single-crystal X-ray,
and FTIR study. Mitt ÖMG, 141, 168 - 169, abstract
Libowitzky
E (1997) Wasserstoff-Unordnung und Phasenumwandlungen in Lawsonit
und Hemimorphit. Habilitationsschrift, Universität Wien
Libowitzky
E, Rossman GR (1997) IR spectroscopy of hemimorphite between
82 and 373 K and optical evidence for a low-temperature phase
transition. Eur J Mineral, 9, 793-802
Libowitzky
E, Kohler T, Armbruster T, Rossman GR (1997) Proton disorder
in dehydrated hemimorphite - IR spectroscopy and X-ray structure
refinement at low and ambient temperatures. Eur J Mineral, 9,
803-810
Kohler
T, Armbruster T, Libowitzky E (1997) Hydrogen bonding and Jahn-Teller
distortion in groutite, -MnOOH, and
manganite, -MnOOH, and
their relations to ramsdellite, -MnO2, and
pyrolusite, ß-MnO2. J Solid State
Chem, 133, 486-501
Libowitzky
E, Rossman GR (1997) Infrared spectroscopy: A quantitative approach
to water in minerals. Ber DMG - Beih Eur J Mineral, 9, 222, abstract
Libowitzky
E, Armbruster T, Beran A, Giester G, Hammer VMF, Hoffmann C,
Kunz M, Nyfeler D, Rossman, GR (1997) Infrared spectroscopy of
very strong hydrogen bonds in minerals. Ber DMG - Beih Eur J
Mineral, 9, 221, abstract
Nyfeler
D, Hoffmann C, Armbruster T, Kunz M, Libowitzky E (1997) Orthorhombic
Jahn-Teller distortion and Si-OH in mozartite CaMn3+O[SiO3OH]: A
single-crystal X-ray, FTIR, and structure modeling study. Am
Mineral, 82, 841-848
Libowitzky
E, Rossman GR (1997) An IR absorption calibration for water in
minerals. Am Mineral, 82, 1111-1115
Libowitzky
E, Beran A (1997) Hydrogen and hydrogen bonds in minerals. XIIth
Conference "Horizons in Hydrogen Bond Research". Abstract
Beran
A, Giester G, Libowitzky E (1997) The hydrogen bond system in
natrochalcite-type compounds - An FTIR spectroscopic study of
the H3O2- unit. Mineral Petrol,
61, 223-235
Hammer
VMF, Libowitzky E, Rossman GR (1998) Single-crystal IR spectroscopy
of very strong hydrogen bonds in pectolite, NaCa2[Si3O8(OH)], and
serandite, NaMn2[Si3O8(OH)]. Am
Mineral, 83, 569-576
Libowitzky
E, Schultz AJ, Young DM (1998) The low-temperature structure
and phase transition of hemimorphite, Zn4Si2O7(OH)2 · H2O. Z
Krist, 213, 659-668
Libowitzky
E (1998) Wasserstoff und Wasserstoffbrücken in Mineralen.
Mitt ÖMG, 143, 41 - 53
Armbruster
T, Birrer J, Libowitzky E, Beran A (1998) Crystal chemistry of
Ti-bearing andradites. Eur J Mineral, 10, 907 - 921
Libowitzky
E (1998) OD-Charakter der Hemimorphitstruktur bei 20 K: Strukturuntersuchung
mit TOF-Neutronen. Mitt ÖMG, 143, 332 - 333, abstract
Lager
GA, Libowitzky E, Schultz AJ (1998) Neutron diffraction study
of the low-temperature phase transitions in lawsonite. IMA98,
A99, abstract
Libowitzky
E (1999) Correlation of O-H stretching frequencies and O-H···O
hydrogen bond lengths in minerals. Mh Chemie, 130, 1047 - 1059
Beran
A, Libowitzky E (1999) IR spectroscopy and hydrogen bonding in
minerals. In: Wright K, Catlow R (eds) (1999) Microscopic properties
and processes in minerals. Kluwer Academic Publishers, Netherlands
, 493 - 508
Libowitzky
E (1999) Comparison of hydrogen bond distance - frequency correlations
in solids. Ber. DMG - Beih Eur J Mineral, 11, abstract, in press
Hertweck
B, Libowitzky E, Giester G (1999) Phase transitions in leonite-type
compounds. Ber. DMG - Beih Eur J Mineral, 11, 104. Abstract
Sondergeld
P, Schranz W, Kityk AV, Carpenter MA, Libowitzky E (2000) Ordering
behaviour of the mineral lawsonite. Phase Transitions, Part B,
71, 189 - 203
Sondergeld
P, Schranz W, Tröster A, Carpenter MA, Libowitzky E, Kitijk
AV (2000) Optical, elastic, and dielectric studies of the phase
transitions in lawsonite. Phys Rev B, 62, 6143 - 6147
Libowitzky
E (2000) Phase transitions in minerals: Correlation of spectroscopic
and diffraction data. 19th Eur Cryst Meeting Astracts,
137. Abstract
Libowitzky
E, Giester G (2000) The crystal structure of soda at 110 K and
270 K. 19th Eur Cryst Meeting Astracts, 341. Abstract
Hertweck
B, Armbruster T, Libowitzky E (2000) A single-crystal study of
the low-temperature phase transitions in leonite-type compounds.
19 th Eur Cryst Meeting Astracts, 362. Abstract
Armbruster
T, Kohler T, Libowitzky E, Friedrich A, Miletich R, Kunz M, Medenbach
O, Gutzmer J (2001) Structure, compressibility, hydrogen bonding,
and dehydration of the tetragonal Mn 3+ hydrogarnet, henritermierite.
Am Mineral, 86, 147 - 158
Hertweck
B, Libowitzky E (2001) IR and Raman spectroscopy of the phase
transitions in leonite-type compounds. Bull Liaison SFMC, 13,
80. Abstract
Hertweck
B, Libowitzky E, Schultz AJ (2001) Neutron diffraction study
of the low-temperature phase transitions of Mn-leonite. Mitt Österr
Miner Ges, 146, 109 - 110. Abstract
Hertweck
B, Libowitzky E, Giester G (2001) The crystal structures of the
low-temperature phases of leonite-type compounds, K2Me(SO4)2×4H2O
(Me2+ = Mg, Mn, Fe). Am Mineral, 86, 1282 - 1292
Nasdala
L, Beran A, Libowitzky E, Wolf D (2001) The incorporation of
hydroxyl groups and molecular water in natural zircon (ZrSiO4),
Am J Sci, 301, 831 - 857
Szalay
V, Kovács L, Wöhlecke M, Libowitzky E (2002) Stretching
potential and equilibrium length of the OH bond in solids. Chem
Phys Lett, 354, 56 - 61
Hertweck
B, Armbruster T, Libowitzky E (2002) Multiple phase transitions
of leonite-type compounds: optical, calorimetric, and X-ray data.
Mineral Petrol, 75, 245 - 259
Libowitzky
E(2002) Hydrogen bonding in minerals and inorganic materials.
SGK/SSCr Newsletter, 56 and 57, 7. Abstract
Hertweck
B, Libowitzky E (2002) Vibrational spectroscopy of phase transitions
in leonite-type minerals. Eur J Mineral, 14, 1009 - 1017
Beran
A, Libowitzky E (2003) IR spectroscopic characterization of OH
defects in mineral phases. Phase Trans, 76, 1 - 15
Halmer
MM, Libowitzky E, Beran A (2003) IR spectroscopic determination
of OH defects in spinel group minerals. Geophys Res Abstr, 5,
06742. Abstract
Libowitzky
E , Giester G (2003) Washing soda (natron), Na2CO3×10H2O,
revised: Crystal structures at low and ambient temperatures.
Mineral Petrol, 77, 177 - 195
Giester
G, Libowitzky E (2003) Crystal structures and Raman spectra of
Cu(OH)F and Cu3(OH)2F4. Z Kristallogr,
218, 351 - 356
Libowitzky
E (2003) Hydrogen and hydrogen bonds in minerals. Book of Abstracts,
46, LERM 2003, Nove Mesto (CZ). Abstract
Halmer
MM, Beran A, Libowitzky E (2003) Detecting OH defects in iron-bearing
( IVFe2+) spinel phases by IR spectroscopy.
Book of Abstracts, 27, LERM 2003, Nove Mesto (CZ). Abstract
Hertweck
B, Libowitzky E, Schultz AJ(2003) The hydrogen bond system of
Mn-leonite: neutron diffraction results in comparison with IR
spectroscopic data. Z Kristallogr, 218, 403 - 412
Halmer
MM, Libowitzky E, Beran A (2003) IR spektroskopische Untersuchungen
von OH-Defekten in eisenhaltigen ( IVFe2+)
Spinellphasen. Mitt Österr Miner Ges, 148, 156. Abstract
Libowitzky
E, Beran A (2004) IR spectroscopic characterisation of hydrous
species in minerals. In: Beran A, Libowitzky E (eds) (2004) "Spectroscopic
Methods in Mineralogy", EMU Notes in Mineralogy 6, 227 -
279
Beran
A, Libowitzky E (eds) (2004) "Spectroscopic Methods in Mineralogy",
EMU Notes in Mineralogy 6, 661 pp
Mihajlovic
T, Libowitzky E, Effenberger H (2004) Synthesis, crystal structure,
infrared and Raman spectra of Sr 5(As 2O 7) 2(AsO 3OH). Mitt Österr
Miner Ges 149, 67. Abstract
Bellatreccia
F, Della Ventura G, Libowitzky E, Beran A, Ottolini L (2004)
A calibration curve for the OH content in vesuvianite: a polarized
single-crystal FTIR study. Mitt Österr Miner Ges 149, 14.
Abstract
Bellatreccia
F, Della Ventura G, Libowitzky E, Beran A (2004) The quantitative
determination of B and H in vesuvianite: an FTIR spectroscopic
study. 32 nd Int Geol Congress, Florence , G04.02. Abstract
Mihajlovic
T, Libowitzky E, Effenberger H (2004) Synthesis, crystal structure,
infrared and Raman spectra of Sr 5(As 2O 7) 2(AsO 3OH). J Solid
State Chem, in press
Bellatreccia
F, Della Ventura G, Ottolini L, Libowitzky E, Beran A
(2004) The quantitative analysis of OH in vesuvianite: a polarized
FTIR and SIMS study. Phys Chem Minerals, submitted
Miscellaneous
Papers (ore microscopy, field mineralogy, crystal chemistry,
etc.)
Libowitzky
E (1985) Auflichtoptische Untersuchungen an Ruthenium. Diplomarbeit,
Univ. Vienna , 1985
Libowitzky
E (1986) A reflected light investigation of ruthenium. Tschermaks
Min Petr Mitt 35, 27-32
Libowitzky
E (1987) Auflichtoptische Untersuchungen an Osmium. Anz österr
Akad Wiss, math-nawi Kl 124, 101-104
Libowitzky
E (1987) Auflichtoptik von Ruthenium und Osmium. Mitt. der SGK
10, P004. Abstract
Libowitzky
E (1989) Mineralogische Untersuchung einer magnetischen Anomalie
im Moravikum der Böhmischen Masse in Österreich. PhD
thesis, Univ. Vienna, 1989
Libowitzky
E (1989) "Dreieck", a simple BASIC-program for plotting
triangular concentration diagrams on IBM (XT/AT)-compatible personal
computer systems. Mineral Petrol 41, 257-258
Libowitzky
E (1989) Magnetite and ilmenite bearing chlorite-schists in the
Moravian zone of the Bohemian massif in Austria. Terra abstr.
1, S10/14. Abstract
Libowitzky
E (1990) Precambrian blacksands as precursors of magnetite and
ilmenite bearing chlorite-micaschists, Bohemian massif, Austria
. Mineral Petrol 43, 147-160
Libowitzky
E, Götzinger MA (1993) Codazzit, ein SEE-reicher Ankerit
aus Muzo, Columbien, ist ein SEE-freier Dolomit. Berichte der
DMG 1, 1993 (Add. Vol. Eur J Mineral 5), KC-III-4, 162. Abstract
Libowitzky
E , Götzinger MA (1993) Codazzite from Muzo , Colombia :
Pure dolomite without REE. N Jb Miner Mh, 1993/12, 542 - 546
Libowitzky
E, Giester G, Tillmanns E (1994) Zur Kristallchemie des neuen
Sulfosalzminerals Jankovicit,Tl 5Sb 9( As,Sb) 4S 22. Mitt Österr
Miner Ges, 139, 333 - 335. Abstract
Libowitzky
E, Giester G, Tillmanns E (1994) Jankovicite, a new sulfosalt
mineral from Allchar, Macedonia: Crystal structure and crystal
chemistry. IMA 1994, Abs. Vol., 242 - 243. Abstract
Ertl
A, Libowitzky E, Pertlik F (1994) Chemische und röntgenkristallo-graphische
Untersuchungen an Eskimoit (Ag 7Pb 10Bi 15S 36) und Heyrovskyit
(AgPb 10Bi 5S 18) vom Rauriser Goldberg, Hüttwinkeltal,
Land Salzburg. Mitt Österr Miner Ges, 139, 135 - 142
Götzinger
MA, Beran A, Libowitzky E (1994) Exkursion A: Mineralvorkommen
und Lagerstätten im östlichen Waldviertel. Mitt Österr
Miner Ges, 139, 389 - 405
Libowitzky
E , Giester G, Tillmanns E (1995) The crystal structure of jankovicite,
Tl5Sb9( As,Sb)4S22.
Eur J Mineral, 7, 479 - 487
Cvetcovic
L, Boronikhin VA, Pavicevic MK, Krajnovic D, Grzetic I, Libowitzky
E, Giester G, Tillmanns E (1995) Jankovicite, Tl5Sb9(As,Sb)4S22,
a new sulfosalt from Allchar, Macedonia. Mineral Petrol, 53,
125 - 131
Wohlschläger
A, Kolitsch U, Libowitzky E (2001) Large "gahnites" from
near Okahua, Namibia: only Fe- and Zn-bearing spinels. Mitt Österr
Miner Ges, 146, 323. Abstract
Guscik
A, Koeberl C, Brandstätter F, Reimold WU, Libowitzky E (2002)
Cathodoluminescence, electron microscopy, and Raman spectroscopy
of shock-methamorphosed zircon. Earth Planet Sci Lett, 202, 495
- 509
Schwendtner
K, Libowitzky E, Götzinger MA, Koss S (2003) Quantitative
FT-IR spectroscopy of gypsum raw material for industry. Geophys
Res Abstr, 5, 06826. Abstract
Lukács
R, Libowitzky E, Harangi S, Ntaflos T (2003) Magma chamber processes
in the miocene silicic pyroclastic suites of the Bükkalja
volcanic field (northern Hungary) revealed by silicate melt inclusions
in lithic clasts. Acta Miner Petrogr, Abstr Ser, 2, 118 - 119.
Abstract
Schwendtner
K, Libowitzky E, Götzinger MA, Koss, S (2003) FT-IR-Spektroskopische
Quantifizierungen am Gips/Anhydrit-Rohstein des Bergbaus Puchberg
am Schneeberg. Mitt Österr Miner Ges, 148, 286 - 287. Abstract
Gucsik
A, Koeberl C, Brandstätter F, Libowitzky E (2003) Cathodoluminescence
and Raman studies of impact glasses. 66 th Annual Meteoritical
Society Meeting (2003), Münster. Abstract #5217
Gucsik
A, Koeberl C, Brandstätter F, Libowitzky E, Reimold WU (2003)
Scanning electron microscopy, cathodoluminescence, and Raman
spectroscopy of experimentally shock metamorphosed quartzite.
Meteoritics and Planetary Sciences, 38, 1187 - 1197
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A, Koeberl C, Brandstätter F, Libowitzky E, Reimold WU (2004)
Cathodoluminescence, electron microscopy, and Raman spectroscopy
of experimentally shock metamorphosed zircon crystals and naturally
shocked zircon from the Ries impact crater. In: Dypvik H, Burchell
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in rock-forming minerals. Mineral Petrol 81, 203
Gucsik
A, Koeberl C, Brandstätter F, Libowitzky E, Zhang M (2004)
Infrared, Raman, and cathodoluminescence studies of impact glasses.
Meteoritics and Planetary Sciences ..., in press
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