The story
- Middle High Germankobe
- Middle High Germanhold
- Middle High German*holt
- GermanKobold
- GermanKobalt
- English todaycobalt
From German Kobalt, formerly also Kobald, ‑olt, ‑old, ‑elt, ‑el, apparently the same word as Kobold (“goblin”), from Middle High German, which became also a Harz Mountains silver miners’ term for rock laced with arsenic and sulfur, so called because it degraded the ore and made the miners ill. Doublet of kobold.
Etymology from Wiktionary, CC BY-SA 4.0.