Martin goes in search of Na2B4O7 with traces of CuSO4. Na2B4O7 is borax, mined by the kiloton in California and sold nationwide in every store that carries laundry detergent. CuSO4 is copper(II) sulfate, one of the most common copper compounds around, found at every medical lab, Red Cross blood drive, hardware store, vineyard, gardening center, and on every penny that is not bright and shiny.