Ezad, Isra S.Shcheka, Svyatoslav S.Buhre, StephanBuhre, AndreasGorojovsky, Lauren R.Shea, Joshua J.Forster, Michael W.Foley, Stephen2024-09-082024-09-080034-6748https://hdl.handle.net/1885/733716194The accurate and precise determination of the compositions of silicate glasses formed from melts containing volatile components H2O and CO2 recovered from high-pressure, high-temperature experiments is essential to our understanding of geodynamic processes taking place within the planet. Silicate melts are often difficult to analyze chemically because the formation of quench crystals and overgrowths on silicate phases is rapid and widespread upon quenching of experiments, preventing the formation of glasses in low-SiO2 and volatile-rich compositions. Here, we present experiments conducted in a novel rapid quench piston cylinder apparatus on a series of partially molten low-silica alkaline rock compositions (lamproite, basanite, and calk-alkaline basalt) with a range of water contents between 3.5 and 10 wt %. Quench modification of the volatile-bearing silicate glasses is significantly reduced compared to those produced in older piston cylinder apparatuses. The recovered glasses are almost completely free of quench modification and facilitate the determination of precise chemical compositions. We illustrate significantly improved quench textures and provide an analytical protocol that recovers accurate chemical compositions from both poorly quenched and well-quenched silicate glasses.The prototype RQPC, designed by Stephan and Andreas Buhre, was built at the Geocycles Earth System Science Research Centre of the Johannes Gutenberg University of Mainz, funded by the State of Rhineland-Palatinate. The Macquarie instrument was funded by Macquarie University in support of the Australian Research Council Laureate Fellowship to S.F.F. The authors wish to thank Sean Murray for his help with imaging on the FE-SEM at Macquarie University and Sandrin Feig for his assistance with FE-EMPA data collection at the University of Tasmania.application/pdfen-AU© 2023 The authorshttp://creativecommons.org/licenses/by/4.0/202310.1063/5.01294172024-04-21Creative Commons Attribution licence