Erbium

Erbium is the third element named after the village of Ytterby, Sweden. Discovered in 1842 by Carl Gustaf Mosander, erbium is a silvery metal with a slight pinkish tint. When erbium compounds are added to glass, they produce a beautiful pink color — erbium-doped glass is used in decorative glassware and some sunglasses.

Erbium's most important modern application is in fiber optic telecommunications. Erbium-doped fiber amplifiers (EDFAs) boost light signals traveling through fiber optic cables, allowing internet data to travel thousands of kilometers under the ocean without degrading. Without erbium, the internet as we know it would be much slower. Erbium lasers are also used in dermatology for skin resurfacing treatments.

Erbium's symbol 'Er' is one of the most valuable two-letter elements in Spellement. It matches the ending of hundreds of English words like 'water,' 'never,' and 'power,' and starts words like 'era' and 'error.' This incredible frequency makes erbium a word-building champion.