Extractions of nucleic acids, proteins, metabolites and other small molecules from samples 1/4" Ceramic Sphere is a zirconium oxide coated grinding matrix which is chemically inert 1/4" Ceramic Sphere is used to break hard and brittle samples. This includes RNA extraction from difficult samples where lysis by impaction only is preferable with minimal amounts of mechanical shearing Bead Material Zirconium oxide coated ceramic Bead Size 6.35 mm (1/4 inch)