A Potential New Chalcopyrite Reference Material for LA‐MC‐ICP‐MS Copper Isotope Ratio Measurement

Abstract

A new natural chalcopyrite reference material TC1725 is prepared for in situ Cu isotope measurement by femtosecond laser ablation multi‐collector inductively coupled plasma‐mass spectrometry (fsLA‐MC‐ICP‐MS). Detailed textural examination and major element determination suggest the TC1725 chalcopyrite grains have no growth rim or zoning. The chalcopyrite grain is homogeneous with respect to Cu isotopes based on a large number of measurements performed by bulk solution nebuliser (SN)‐MC‐ICP‐MS, single‐grain SN‐MC‐ICP‐MS and fsLA‐MC‐ICP‐MS. The traditional bulk isotope analyses by SN‐MC‐ICP‐MS yielded a mean δ65Cu value of −0.06 ± 0.03‰ (2s, n = 132). Randomly selected single chalcopyrite grain of TC1725 determined by SN‐MC‐ICP‐MS without column chromatography gave a mean δ65Cu value of −0.06 ± 0.04‰ (2s, n = 188). The intermediate measurement precision for four measurement sessions was better than 0.04‰ (2s), suggesting TC1725 chalcopyrite is suitable as a microanalysis reference material for Cu isotope measurement. The mean δ65Cu value determined by fsLA‐MC‐ICP‐MS analyses on different individual chalcopyrite mounts and strips was −0.06 ± 0.03‰ (2s, n = 393), consistent with the bulk isotope composition within uncertainty. The recommended mean δ65Cu value for this chalcopyrite reference material is −0.06 ± 0.03‰ (2s, n = 132) as determined by bulk SN‐MC‐ICP‐MS.

Atomic spectrometry update – a review of advances in environmental analysis

“…The recommended d 34 S value determined by IRMS was +0.63 AE 0.16& (2SD, n ¼ 23). Another chalcopyrite RM (TC1725) was described 216 for in situ Cu isotope ratio measurements by LA-MC-ICP-MS. Homogeneity was evaluated by solution MC-ICP-MS analysis of bulk material and single grains as well as by fs LA-MC-ICP-MS. Results from all analytical methods agreed within uncertainties.…”

Geostandards and Geoanalytical Research Bibliographic Review 2021

“…For example, a new natural chalcopyrite reference material – TC1725 – has been prepared for in situ Cu isotope measurement by Bao et al . (2021). Chen et al .…”

“…Some minerals are proposed as RMs especially for specific isotopic systems to broaden the selection of matrix-matched RMs. For example, a new natural chalcopyrite reference material -TC1725has been prepared for in situ Cu isotope measurement by Bao et al (2021). Chen et al (2021) introduced natural pyrrhotite (JC-Po) and pentlandite (JC-Pn) from the Jinchuan Ni-Cu-PGE massive sulfide ores (China) which have been evaluated as S and Fe isotope RMs.…”

A new potential natural chalcopyrite reference material for in situ copper isotope microanalysis

“…14 Although it is a powerful and efficient analytical technique, the matrix effect during LA-MC-ICP-MS analyses may cause signicant Cu isotope fractionation, and matrix-matched reference materials are essential to eliminate the matrix effect and obtain accurate data. 1,15 In terms of the potential chalcopyrite reference material for in situ Cu isotope analyses, there is currently only one well-characterized and highquality specimen (TC1725), 16 and hence more chemically and isotopically homogeneous chalcopyrite reference materials need to be developed for Cu isotope microanalysis and data traceability between different laboratories.…”