Starting in 2019 alarm bells were rung when sampling of tap water in Europe turned up traces of gadolinium. Papers in trade journals quickly followed confirming the presence of this metal in humans, particularly in the brain and bones. However, the hubbub dispersed as quickly as it appeared when ailments related to this new boogeyman failed to turn up.

A likely reason could be a simple case of poor inter-disciplinary training. Even beginning chemistry textbooks point out the extreme similarity of the lanthanides, meaning that wherever one stumbles on gadolinium the other rare earths can be expected to be found as well and that they can be expected to have more or less equal effects in the body whether deleterious or harmless. Happily, it doesn’t seem like any of that alarm was warranted (not that one should treat any exotic material casually!)

Aaaaanyway, here we have the most highly refined version of this metal. Slightly yellow, gadolinium in this format consists of tightly clumped tendrils sometimes in cakes or sheets and at others more lamellar and chunky - altogether a slight but noticeable difference that is sufficient to tell them apart at a glance.