Abstract: A glass grinder for breaking glass from particle or fragment configuration to a grit of a predetermined size. The grinder employs a grinding chamber having an upper and lower portion wherein glass fragments are broken into relatively large particulate size in the upper chamber and passes into the lower chamber where glass is further impacted by blades and driven into a peripheral dam of glass particles. As the glass impacts the dam, it is further broken down to the desired grit size. Overflow from the grit dam exits the chamber under a reduced pressure to control dust production.