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Updated: May 21, 2026
09:31
Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS
Published on: August 31, 2017
Electron paramagnetic resonance, optical absorption and Raman spectral studies on a pyrite/chalcopyrite mineral
G Udayabhaskar Reddy1, K Seshamaheswaramma, Yoshinobu Nakamura
1Dept. of Physics, S.V.D. College, Kadapa 516 003, India.
Summary
This study characterizes pyrite and chalcopyrite minerals from India using advanced techniques. Findings reveal their crystal structure, particle size, and elemental composition, including iron, copper, and manganese.
Area of Science:
- Mineralogy and Materials Science
- Geochemistry
- Solid State Physics
Background:
- Pyrite and chalcopyrite are significant sulfide minerals with diverse geological occurrences.
- Understanding their physical and chemical properties is crucial for mineral exploration and material applications.
- The Mangampet barite mine provides a unique geological context for studying these minerals.
Purpose of the Study:
- To comprehensively characterize pyrite and chalcopyrite mineral samples.
- To determine the structural, compositional, and electronic properties of the minerals.
- To investigate the presence of impurities and associated ions within the mineral matrices.
Main Methods:
- X-ray Diffraction (XRD) for crystal structure and particle size analysis.
- Electron Paramagnetic Resonance (EPR) spectroscopy to identify paramagnetic species.
- Optical Absorption Spectroscopy to probe electronic transitions and coordination environments.
- Near-Infrared (NIR) and Raman Spectroscopy for identifying molecular vibrations and functional groups.
Main Results:
- Pyrite exhibits a face-centered cubic lattice structure with a lattice constant of 5.4179 Å and an average particle size of 91.9 nm.
- EPR studies confirmed the presence of iron in pyrite, and iron along with Mn(II) in chalcopyrite.
- Optical absorption and spectroscopic analyses indicated the presence of copper in a distorted octahedral environment, along with water and sulfate ions.
Conclusions:
- The study successfully elucidated the detailed structural and compositional characteristics of pyrite and chalcopyrite.
- The presence of specific elements and ions (Fe, Cu, Mn(II), H2O, SO4^2-) was confirmed using a multi-spectroscopic approach.
- These findings contribute to a better understanding of sulfide mineralogy and their potential applications.
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