We are deeply saddened to share the news of the early passing of Professor Dr Selahattin Kadir on 27 March 2025; he was a retired (March 2023) lecturer from the Department of Geological Engineering at the Eskişehir Osman Gazi University (Türkiye). He made valuable contributions to his University through his dedication to the academic development of his students and as a hard-working and effective administrator.
Professor Kadir was one of the founder members and a devoted executive committee member of the Turkish Clay Science Society. He worked hard to ensure the success of the Society and to enable it to achieve its goals effectively.
Selahattin’s family came from Kerkük in northern Iraq, where a large population of Turks are settled. Selahattin had his early education (six years of preliminary school, three years of middle school, and three years of high school) in Kerkük through both Arabic and English. Following graduation, he moved to Türkiye for his higher University education. He attended the Geological Engineering Department of Karadeniz Technical University at Trabzon (NE Black Sea).
Selahattin was a professor of Mineralogy and Petrography. He held a BSc in geology from Karadeniz Technical University, an MSc from Ankara University, and a PhD from Selçuk University, all in Türkiye.
He joined the Phelps Dodge Corporation (1985–1987) for an advanced feasibility study of a Kuruko-type Massive Sulphide Orebody Project; Parsons Brinckerhoff International, Inc. (1987–1989) for a geological surveying project for a motorway; and the General Directorate of Mineral Research and Exploration of Turkey (1990–2004) as an exploration/research geologist. He was employed by the Eskişehir Osmangazi University (ESOGU) from 2004 as an academic staff member of the Department of Geological Engineering. He served as the Director of the Technological Research Center of ESOGU (2010–2014) and was Chairman of the Department of Geological Engineering between 2015 and 2024.
Selahattin built his research career mainly on the mineralogical and geochemical characteristics, and genesis of hydrothermal and diagenetic kaolinite, bentonite, and sepiolite-palygorskite deposits/occurrences, lateritic-weathering-related Ni-Co deposits, and alterations in massive sulfide ores and gold deposits. He also worked on interdisciplinary aspects of mineralogy, geochemistry, and genesis of calcretes, dolocretes, huntites, magnesites, paleosols, and evaporites in sediments and soils. His reseach topics included the relationship between asbestos and development of mesothelioma. Selahattin managed and successfully completed numerous scientific projects. He published more than 70 peer-reviewed papers (SCI), seven book chapters, and made 80 oral presentations at international conferences.
Professor Kadir was the Secretary of the Euroclay 2011 conference (Antalya) and served as a loyal Associate Editor of Clays and Clay Minerals since 2011. As a Guest Editor, he organized special issues on the ‘Pedology and Morphology/Micromorphology of Soils’ (Euroclay 2011) and ‘Eurosoil 2016’ in the Turkish Journal of Earth Sciences and Catena, respectively. He acted as a member of Source Clays Committee of The Clay Minerals Society (USA) (2016–2017) and on the Program Development Committee. Selahattin co-chaired the 17th International Clay Conference during 2022 in İstanbul (co-organized by The Clay Science Society (Türkiye) and The Clay Minerals Society (USA)). A successful event was achieved in the face of difficulties imposed by the global pandemic.
We extend our sincere condolences to his grieving family and the entire Clay Community.
