A compact, low cost screw-press designed to pulverize 50-500mg of hard, brittle material such as bone or teeth. If fresh tissue is used, the sample is cooled in liquid nitrogen to make the tissue hard and brittle, inserted into in the pre-cooled pulverizer 'nut' and then crushed by manually screwing together the two screw plungers. The end result is tissue powdered to the size of grains of table salt or smaller. Use as a preliminary step to homogenization or extraction which then will proceed quickly and efficiently using one of several standard cell disruption methods. For cryo-pulverization of soft or elastic tissue, see the BioPulverizer.