Shaping particles for ultramicrotomy

In this paper a technique for preshaping large particles of reacted glass for ultramicrotomy is described. This technique preserves delicate surface layers and results in more sections per block extending deeper into the sample than other techniques. The samples of interest in this laboratory are simulated nuclear waste glasses which have been aged either in a water vapor environment like that expected at the potential high level nuclear waste repository or in a liquid water environment. Reaction layers develop on the surface of the glass resulting form the deposition of material from the surrounding solution and/or alteration and in situ restructuring of the glass structure