232,993. Hartstoff-Metall Akt.-Ges. Hametag. April 28, 1924, [Convention date]. Reducing to powder by aid of special solutions. -In a process for the production of fine powders, particularly metallic powders, by causing the particles of the substance to be pulverized to collide repeatedly against each other through the action of fluid eddies, a small quantity of a lubricant substance, preferably of an organic nature such as fat, oil, wax, paraffin stearine or the like, which spreads over the particles during the grinding or pulverizing process in the form of a thin laver or film is added to the substance to be pulverized. The lubricant may be fed continuously into the mill during the operation of the mill, or it may be mixed with the substance to be pulverized before the substance is placed in the mill. If olive oil is added to aluminium, a powder is obtained whose particles are substantially ball-shaped; with an admixture of paraffin substantially leaf-shaped particles will be formed. The lubricant mav be removed from the finished powder by washing or steaming.