SEM TECH (Salt Electro Mining Technology) is an open-source electrochemical mining and refining system built by Rowow LLC in Lake Wales, Florida. It recovers critical minerals, precious metals, and rare earth elements from ores, mine tailings, slags, and e-waste using DIY ion exchange membranes and electrolysis cells that regenerate their own acids on site. Membrane recipes, cell designs, and process documentation are released under CERN-OHL-S. Funds raised here buy lab equipment, materials, and consumables for the continuous pilot, and every result is published free. Build guides at github.com/Rowow-LLC and youtube.com/@Rowow.