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We present a new set of reference materials, the ND70‐series, forin situmeasurement of volatile elements (H₂O, CO₂, S, Cl, F) in silicate glass of basaltic composition. The materials were synthesised in piston cylinders at pressures of 1 to 1.5 GPa under volatile‐undersaturated conditions. They span mass fractions from 0 to 6%m/mH₂O, from 0 to 1.6%m/mCO₂and from 0 to 1%m/mS, Cl and F. The materials were characterised by elastic recoil detection analysis for H₂O, by nuclear reaction analysis for CO₂, by elemental analyser for CO₂, by Fourier transform infrared spectroscopy for H₂O and CO₂, by secondary ion mass spectrometry for H₂O, CO₂, S, Cl and F, and by electron probe microanalysis for CO₂, S, Cl and major elements. Comparison between expected and measured volatile amounts across techniques and institutions is excellent. It was found however that SIMS measurements of CO₂mass fractions using either Cs⁺or O⁻primary beams are strongly affected by the glass H₂O content. Reference materials have been made available to users at ion probe facilities in the US, Europe and Japan. Remaining reference materials are preserved at the Smithsonian National Museum of Natural History where they are freely available on loan to any researcher. 

Minor and trace elements in diamond-like carbon (DLC) are difficult to quantify using SIMS analysis because minor elemental and structural variations can result in major matrix effects even across individual, cm-sized samples. While this material is most commonly used for tribological coatings where minor element composition is not of critical importance, it is being increasingly used in electronic devices. However, it is a unique application that spurred this work: anhydrous, tetrahedrally-coordinated DLC (ta-C) was used as a solar wind (SW) collector material in the Genesis solar-wind sample return mission (NASA Discovery 5). So, for ∼15 years, we have been working on attaining accurate and precise measurement of minor and trace elements in the Genesis DLC using SIMS to achieve our mission goals. Specifically, we have learned to deal with relevant matrix effects in our samples, ion implants into ta-C. Our unknown element for quantification is SW Mg, a low-dose (1.67 × 10 12 at cm −2 ; ∼6 μg g −1 24 Mg), low-energy (∼24 keV average energy) implant; our standard is a high-dose (∼1 × 10 14 at cm −2 of both 25 Mg, 26 Mg) 75 keV laboratory implant for which the absolute 26 Mg/ 25 Mg ratio had been measured to account for variable instrumental mass fractionation. Analyses were performed using O 2 + primary ions having both a low impact energy and a current density of ∼2 × 10 14 ions per cm 2 . Although our unknown was solar wind, the method is applicable to many situations where minor elements in DLC need to be quantified. Recommendations are presented for modifying this data-reduction technique for other SIMS conditions.