The HMXST Micro-CT x-ray imaging system produces three dimensional images of biological, art, minerals and electronic component materials. The x-ray cabinet accommodates specimens up to 8inchx8inch maximum cross section. The system is outfitted with an open source x-ray tube that has a maximum resolution of 3-5 microns in reflection mode and 2 microns in transmission mode. The system has a Mo, W, Ag, and Cu x-ray targets. A Perkin Elmer 1621 x-ray panel provides 2000×2000 pixel 16inchx16inch field of view with 7.5 frames per second readout and a physical pixel size of 200 microns. The micro-CT computer system consists of three 64 bit computers and software consisting of (1) control and data acquisition, (2) three-dimensional reconstruction, and (3) a visualization station.