Very sad to hear this. Indeed a legend. I loved the movie they used to show at the Smithsonian Museum with him. He is in a chef’s outfit and “cooking” petrological experiments. Andreas ——————————————————————— Dr. Andreas Möller (Associate Professor – Geochronology) Department of Geology The University of Kansas 1420 Naismith Dr., Slawson Hall G186 Lawrence, KS 66045 - USA - +1 (785) 864-1447 amoller@ku.edu https://geo.ku.edu/people/andreas-moller * Chair of Graduate Admission - Geology * President – KU International Faculty and Staff Council From: "msa-talk@minlists.org" <msa-talk@minlists.org> Reply-To: Barbara L Dutrow <dutrow@lsu.edu> Date: Thursday, May 15, 2025 at 11:03 AM To: "msa-talk@minlists.org" <msa-talk@minlists.org> Cc: Mark Holdaway <mark@markholdaway.com>, "Gregory, Robert" <bgregory@mail.smu.edu> Subject: [MSA-talk] Mike Holdaway Dear Colleagues, With sadness, we announce the passing of a metamorphic petrology legend, Michael J. Holdaway. He passed peacefully in the early morning of March 21, 2025, at the age of 89. Mike is perhaps best known for his meticulous experiments on the Al2SiO5 system and for developing the andalusite weight loss method for determining reaction direction. His work provided experimental constraints on the triple point of the polymorphs for the first time. He also conducted field work in New Mexico on triple point rocks, in Maine, and in other areas around the world. His experiments continued throughout his career and ranged from studies in mafic to pelitic systems including cordierite and staurolite. He brought his meticulous approach to petrography, crystal chemical studies, particularly of staurolite and their thermodynamic properties (while inspiring others to study), and geothermobarometry. After Mike retired from Southern Methodist University, a special issue of the American Mineralogist was published in Mike's honor in 2002, volume 87. The introduction to the issue, about Mike, is attached (if the MSA list serve allows attachments). I was fortunate to have worked with Mike in the prime days of metamorphic petrology and mineralogy and am grateful that he introduced me to many of the icons in the field. He made sure to bring his students to the MSA luncheons at GSA where they could expand their network and learn from the best. He also shared with me the wonders of experimental petrology, the double capsule method for buffering fO2, and welding, insisted that I determine Li by the ion microprobe in the 80s. A more complete overview of his contributions will follow. His memorial service will be at United Church of Christ in Longmont, Colorado on May 17, 1pm MDT. The service will be broadcast on Youtube Live, should you wish to join. The YouTube link for Mike’s memorial is: https://www.youtube.com/live/23bcL2696Bk?si=ZxECYTXzSyMWQx9E Mike’s obituary is found at: https://www.legacy.com/obituaries/name/michael-holdaway-obituary?pid=209041348 Sincerely, Barb Dutrow Barb Dutrow, Ph.D. Gerald Cire & Lena Grand Williams Alumni Professor Adolphe G. Gueymard Professor Department of Geology & Geophysics E-235 Howe-Russell Geoscience Complex Louisiana State University Baton Rouge, LA 70803-4101 e-mail: dutrow@lsu.edu ph: 225-578-2525 (office) http://www.geol.lsu.edu/dutrow