Dear Colleagues: Ever wonder why melts and glasses behave the way that they do? Want to have insights into how to predict this behavior? Join us in celebrating the career of University of Toronto Professor Grant Henderson, and his contributions to melt structure, AFM, Raman spectroscopy and Synchrotron-based techniques at Special Session 01 of the 2025 GAC-MAC-IAH-CNC—Geoscience Beyond Boundaries. Where: Ottawa, Ontario, Canada When: May 11-14, 2025 Keynote Speaker: Georges Calas, IMPMC, Sorbonne Université Special Session 01: The structure and properties of silicate melts and glasses: A celebration of the career of Grant Henderson The structure of silicate melts ultimately controls their physical and chemical properties. Physical properties influence such aspects as viscosity, and hence volcano eruption style, whereas chemical properties underlie the thermodynamic behaviour, such as volatile exsolution and the activity and solubility of elemental constituents. An understanding of the mechanisms of melt-related processes guides our safe response to natural volcanic hazards and the design of melt-derived glasses and glass-ceramics. In this context, the session recognizes Prof. Grant S. Henderson, whose five-decade career was dedicated to using the methods of Atomic Force Microscopy and Raman and X-ray absorption spectroscopy to elucidate the structure of natural and synthetic crystals, glasses, and melts. Contributions are solicited from research on experimental, theoretical, and observational studies on all aspects of structure-property relationships in silicate glasses and melts. Abstract submission is now open, see:https://event.fourwaves.com/ottawa2025/pages Hope to see you in Ottawa, Ben Moulton and James Brenan Convenors