The problem with plant materials is their elasticity, which causes problems in ball mills etc. The best solution we have found sofar is cooling the sample down using liquid nitrogen to make it brittle. You can do so using a simple pestle and mortar approach, but when more samples need to be processed a liquid nitrogen mill might be worth its money. A number of 14C labs use mills produced by Spex. They are quite rugged, and don't introduce C. See http://www.spexcsp.com/main.htm Success! Gert van Klinken At 09:26 10.08.99 -0600, you wrote: >Hi All: > > I'm trying to homogenize 30 cm long cattail samples (the leaf >portion, not >the main stalk)) into a fine powder for d15N and d13C analysis. I had some >luck with a ball mill but the rubber/cork gaskets are breaking down and >contaminating the sample. The material is quite fibrous which makes >homogenization difficult. > > Any advice would be appreciate. Please e-mail me direct. Thanks in >advance. > >Jeff > > >****************************** >Jeff Heikoop >EES-1, MS-D462 >LANL >Los Alamos, NM 87545 >----------------------------------- >Phone: (505) 667-8128 >Fax: (505) 665-3285 Dr. Gert Jaap van Klinken 14C AMS Laboratory Max-Planck-Institut für Biogeochemie PO Box 10 01 64 D-07701 Jena Delivery (larger items), and visiting address: Tatzendpromenade 1A D-07745 Jena Tel: (+49 3641) 643708/3806 Fax (+49 3641) 643710