The yellow/blue cube in f102v2

[-JKP-]

In the middle ages (and earlier, dating back to Pliny and probably earlier), they believed that if you properly distilled antimony sulphide (see pic) you could get a red liquid that was supposedly good medicine (as it turns out modern chemists suspect it was the iron impurities in the ore that contributed to the red color and pure antimony didn't work, which is why medieval alchemical experiments had mixed results and the evasive "red elixir" was hard to create).

It was also ground into powder for use as a dark-colored cosmetic.