2024/07/03 by Luc Vrydaghs, Martin J. Hodson, Alicia Van Ham‐Meert +2 · 1 voice
Agricultural and Biological Sciences · Earth and Planetary Sciences · Physics and Astronomy · #Mineralogy and Gemology Studies #Planetary Science and Exploration #Silicon Effects in Agriculture
paper · doi:10.1080/14614103.2024.2367791
openalex publication_date 2024/07/03 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/02
Our previous research from archaeological contexts suggested that phytoliths become autofluorescent when exposed to fire and heat. The present study is an attempt to investigate the conditions under which autofluorescence occurs in the inflorescence bracts of oats (Avena sativa (L.)) when they are heated. Three factors were investigated: temperature; time; and the presence or absence of oxygen. Unheated phytoliths showed no autofluorescence, and oxygen was not required for autofluorescence. We found that some phytoliths become autofluorescent at temperatures as low as 200°C, but at these lower temperatures this is often masked or hidden by organic material and incompletely oxidised material. All phytolith morphotypes, both cell wall and lumen types, fluoresce at temperatures up to 500°C. Melting in our system was observed to begin before 500°C, and at temperatures higher than this most phytoliths were melted, but Rondel seemed to be particularly resistant to heat. They still fluoresce at 900°C after a total heating period of 330 min. The relevance of this work to archaeological contexts is discussed.