Wow that’s sweet, and surprising not gonna lie!) Not useful for me though, due to partial color blindness 
using 4 categories instead:
- pure elements (Cr, Ag, Na etc.)
- 1-stage-to-pure materials (simple compounds which only need to melt/crack/blend mostly oxides sulfides etc.)
- complicated but useful compounds, which need to be well processed
- all other crap
P.s: you know you could paint barrels inside bath with a dye right? 