Which element was originally named 'glucinium'?

Beryllium was originally named “glucinium,” also written “glucinum” or “glucium,” because some of its compounds have a sweet taste. The name was eventually abandoned because tasting chemical compounds is dangerous and because the element’s mineral source provided a clearer name.

Louis-Nicolas Vauquelin discovered the new element’s oxide in 1798 while studying beryl and emerald. The word glucine came from the Greek root meaning “sweet,” referring to the taste of certain beryllium salts. Friedrich Wöhler and Antoine Bussy independently isolated the metal in 1828, after which the name beryllium became increasingly common.

The modern name refers to beryl, the mineral that also produces gemstones such as emerald and aquamarine. Beryllium is a light, stiff metal with atomic number 4, valued in aerospace components, precision instruments, and X-ray windows. Despite the historical name, beryllium compounds are toxic, so the old “sweet” description should never be interpreted as an invitation to taste them.