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Updated: Jul 12, 2026
07:52
A Novel Technique for Raman Analysis of Highly Radioactive Samples Using Any Standard Micro-Raman Spectrometer
Published on: April 12, 2017
Mossbauer spectrometry of lunar samples
Science (New York, N.Y.)
|January 30, 1970
Summary
Nuclear gamma resonance measurements reveal ferrous iron in lunar silicates, ilmenite, and metallic iron. Ferric iron was not significantly detected in lunar fines or rock chips.
Area of Science:
- Geochemistry
- Nuclear Physics
- Materials Science
Background:
- Lunar materials contain various iron-bearing minerals.
- Understanding iron speciation is crucial for lunar geology and resource assessment.
Purpose of the Study:
- To quantify iron speciation in lunar samples using nuclear gamma resonance (NGR) spectroscopy.
- To identify specific iron-containing minerals and phases in lunar fines and rocks.
Main Methods:
- Nuclear gamma resonance (NGR) measurements were performed.
- Transmission geometry was used for lunar fines.
- Scattering geometry was employed for intact lunar rock chips.
Main Results:
- Ferric iron (Fe³⁺) was not detected in significant amounts.
- Ilmenite (FeTiO₃) resonances were observed in all samples.
- Strong ferrous iron (Fe²⁺) resonances were identified in silicates (pyroxenes, olivine, glasses).
- Metallic iron-nickel alloys and troilite (FeS) were detected in lunar fines.
Conclusions:
- Lunar samples predominantly contain ferrous iron within silicate structures and ilmenite.
- NGR spectroscopy effectively differentiates iron oxidation states and mineral hosts in extraterrestrial materials.
- The presence of metallic iron and troilite indicates specific formation or alteration processes in the lunar regolith.
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