Reference materials are key for assessing inter-laboratory variability and measurement quality, and for placing analytical uncertainty bounds on sample analyses. Here, we investigate four years of data resulting from repeated processing of the CRONUS-N reference material for cosmogenic ¹⁰Be and ²⁶Al analyses. At University of Vermont, we prepared a CRONUS-N aliquot with most of our sample batches from 2013 to 2017; these reference material samples were then distributed to four different accelerator mass spectrometry facilities, yielding 73 ¹⁰Be analyses and 58 ²⁶Al analyses. We determine CRONUS-N ¹⁰Be concentrations of (2.26 ± 0.14) x 10⁵ atoms g⁻¹ (n = 73, mean, 1 SD) and ²⁶Al concentrations of (1.00 ± 0.08) x 10⁶ atoms g⁻¹ (n = 58, mean, 1 SD). We find a reproducibility of 6.3% for ¹⁰Be and 7.7% for ²⁶Al (relative standard deviations). We also document highly variable ²⁷Al and Mg concentrations and a ¹⁰Be dispersion twice as large as the mean AMS analytic uncertainty. Analyses of the CRONUS-N material with and without density separation demonstrate that non-quartz minerals are present in the material and have a large impact on measured concentrations of ²⁷Al, ¹⁰Be, and impurities; these non-quartz minerals represent only a very small portion of the total mass (0.6–0.8%) but have a disproportionally large effect on the resulting data. Our results highlight the importance of completely removing all non-quartz mineral phases from samples prior to Be/Al extraction for the determination of in situ cosmogenic ¹⁰Be and ²⁶Al concentrations.

参考材料是评估实验室间变异性和测量质量以及为样品分析设置分析不确定性界限的关键。在这里，我们调查了四年来重复处理 CRONUS-N 参考材料用于宇宙成因¹⁰ Be 和²⁶ Al 分析的数据。在佛蒙特大学，我们用 2013 年至 2017 年的大部分样品批次制备了 CRONUS-N 等分试样；然后将这些参考材料样品分发到四个不同的加速器质谱设备，产生 73 ¹⁰ Be 分析和 58 ²⁶ Al 分析。^{我们确定 (2.26 ± 0.14) x 10 5}个原子 g ^-1的CRONUS-N ¹⁰ Be 浓度（n = 73，平均值，1 SD）和^{26 个}Al 浓度（1.00 ± 0.08）x 10 ⁶个原子 g ^-1（n = 58，平均值，1 SD）。^{我们发现10} Be的重现性为 6.3% ， ²⁶ Al 的重现性为7.7% （相对标准偏差）。我们还记录了高度可变的²⁷ Al 和 Mg 浓度和¹⁰ Be 色散，是平均 AMS 分析不确定度的两倍。对有和没有密度分离的 CRONUS-N 材料的分析表明，非石英矿物存在于材料中，对测量的²⁷ Al, ^{10浓度有很大影响}是和杂质；这些非石英矿物仅占总质量的很小一部分（0.6-0.8%），但对所得数据的影响却不成比例。我们的结果强调了在提取 Be/Al 之前从样品中完全去除所有非石英矿物相以测定原位宇宙成因¹⁰ Be 和²⁶ Al 浓度的重要性。