Hi Bryce, I may have some Okmok 2008 ash I can send you, although I need to see if the samples I have are coarser than 1mm. I have several hundred grams of the finer-grained ash fall, but not as much of the coarser grains. I'll get back to you soon. -Janet -------- Bryce Malton wrote: To whom it may concern, I am a PhD research student in the Lancaster Environment Centre at Lancaster University (UK). My research project is titled “Airborne particle impact on metallic surfaces: an empirical study of the relationship between fracture dynamics and fracto-emission.” This work has been driven by the need to devise a cost effective particle detection system for aviation. Airborne particulates such as volcanic ash, ice and sand represent a significant aviation safety hazard, and yet a robust detection system does not exist. This work may provide the theoretical underpinning for future devices based upon fracto-emission. It also fills a gap in the current research between pure particle fracture dynamics, which resides in the powder processing field, and fracto-emission, which resides in the fields of engineering material failure and physics. The primary aim of the study is to quantitatively explore the relationship between the charge created when an airborne particle impacts a surface and then fractures, and the dynamics driving the fracture of the particle. I would like to investigate particulate samples from a range of sources and I am therefore canvassing for supplies of volcanic ash samples from known eruptions. The sample quantity needs to be enough to sieve a 1mm grain size, perhaps 100 g to 200 g, and from a known eruption. Any data of the chemical composition that is available would be excellent. If you feel you may be able to help please contact me at b.malton1@lancaster.ac.uk or on the UK mobile number below. Regards Bryce Malton Research PhD Student Lancaster Environment Centre Lancaster University Lancaster, LA1 4YQ, United Kingdom Mobile 07802 530044 e-mail b.malton1@lancaster.ac.uk