Order methacrylate balls to use with disposable plastic vials. Disposable grinding vials are ideal for pulverizing soft, brittle materials and for mixing liquids and powders. Vials are also suitable for slurry grinding. Use with Cryo-Block block 04575-85 for preserving temperature sensitive samples during grinding. Ideal for larger samples that are too big for standard titer plates. Vials have been extensively tested with various samples and shown to resist perforation by grinding media. Hardness: Mohs 1 ½ Typical composition: Major Element ? C