Issue 11, 2022

Tianyu-Py pyrite: a new natural reference material for micro-beam determination of iron isotopic ratios

Abstract

The Fe isotopes of bulk Fe sulfides have become useful tracers for understanding geochemical conditions and processes ubiquitously involving Fe during both biological and non-biological processes under various conditions. However, Fe sulfides occur as intergrowth textures in most cases. This gives rise to isotopic results obtained from bulk samples representing a mixed signal. Micro-beam analytical techniques for Fe isotopic analysis using secondary ion mass spectrometry (SIMS) and laser ablation-(multi-collection)-inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) are capable of resolving Fe isotopic variations between natural minerals commonly present as thin lamellae in iron meteorites, micron scale phases in sedimentary, and zonation in hydrothermal deposits. Pyrite is the most common Fe sulfide mineral in igneous, sedimentary, and metamorphic rocks on Earth. In this study, natural pyrite (Tianyu-Py) from the Tianyu magmatic Ni–Cu massive sulfide ores (China) is evaluated as an Fe isotopic RM by multiple methods. Major elements are homogeneously distributed as verified by electron microprobe analyses. The results of LA-MC-ICP-MS iron isotopes prove the homogeneity of Fe isotopes. For in situ microanalysis, the standard deviation of iron isotopic compositions is 0.20‰ (2SD, n = 105) for the δ56Fe value and 0.31‰ (2SD, n = 105) for the δ57Fe value. Based on the solution MC-ICP-MS analyses, the best recommended δ56Fe and δ57Fe values for Tianyu-Py pyrite are 0.49 ± 0.03‰ (2SD, n = 4) and 0.73 ± 0.04‰ (2SD, n = 4), respectively. In summary, the Tianyu-Py pyrite RM is suitable for in situ Fe isotope microanalysis using a laser spot size of 16 μm and is expected to be used for tracking the formation of pyrite precipitation in biological and geological processes.

Graphical abstract: Tianyu-Py pyrite: a new natural reference material for micro-beam determination of iron isotopic ratios

Supplementary files

Article information

Article type
Paper
Submitted
05 Janv. 2022
Accepted
25 Aug. 2022
First published
29 Aug. 2022

J. Anal. At. Spectrom., 2022,37, 2300-2308

Tianyu-Py pyrite: a new natural reference material for micro-beam determination of iron isotopic ratios

L. Chen, Y. Feng, H. Yu, W. Zhang, J. Kang, F. Huang, Z. Hu and X. Li, J. Anal. At. Spectrom., 2022, 37, 2300 DOI: 10.1039/D2JA00002D

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements