The graphite-tipped electrodes were an interesting DIY job themselves, cleverly constructed using copper tubing and a graphite block. The most simple/dangerous/clever part of the whole rig is his ...

D24-C1: Encountered 16.16 metres ("m") grading 0.74% Copper ("Cu") with 533 ppm cobalt ... consistently implemented at this project. NQ drill core was cut into halves for the sample sizes.