Mathieu, hot (>200C) and fluoride containing concentrated phosphoric acid is said to etch glass. Somehow silicon phosphate seems to form, faster with increasing polymerization degree of the acid. [N.H. Ray, The action of phosphoric acid on glass, J.Non-Cryst Solids 5 (1970), 71.] This said, I never observed anything odd with glassware preparing my own acid (H3PO4/P2O5, 240 C, overnight) and less in any carbonate digestion. cheers Chris 2017-02-23 19:00 GMT+11:00 Mathieu Daëron <[log in to unmask]>: > Dear all, > > For years we've been reacting powdered carbonate samples in a common acid > bath at 90 degrees C, with a small, spherical glass bead placed over each > sample to prevent powder projections. I recently realized that I don't know > if these beads are made of soda-lime glass or borosilicate glass. > > Does anyone have words of wisdom to share regarding the chemical > reactivity of soda-lime glass in hot, pure phosphoric acid over durations > of up to 48 hours? > > Thanks in advance, > > – Mathieu Daëron > Centre National de la Recherche Scientifique > Laboratoire des Sciences du Climat et de l'Environnement > -- Please consider the environment before printing this e-mail *University of Tasmania │CSL - Isotope Ratio Mass Spectrometry* Dr. Christian Dietz, Facility Manager *│*Private Bag 74, Hobart, 7005 Tasmania ( Tel: (+61) 3 6226 7820, cell phone: (+61) 4 9780 8570 *│*URL: Central Science Laboratory <http://www.utas.edu.au/research/central-science-laboratory> This message is intended exclusively for its adressee and may contain information that is CONFIDENTIAL and protected by professional privilege. If you are not the intended recipient you are hereby notified that any dissemination, copy or disclosure of this communication is strictly prohibited by law. If this message has been received in error, please immediately notify us via e-mail and delete.