Optimize performance of your Spex SamplePrep Freezer/Mill grinders with a wide range of vial sets suitable for your application. Hardened steel is high durability and efficiency with moderate resistance to abrasion. Ideal for grinding hard, brittle samples to an analytical fineness in the Mixer/Mill grinders. Vial is great for blending powders and mixing emulsions, and is suitable for slurry grinding. Also useful for blending powders and mixing emulsions. Hardness: Mohs 5 ½ - 6; Rockwell ? C 60-65 Typical composition: Major Element ? Fe Minor Elements ? Cr, Si, Mn, C