Erbium turns pink when oxidised, which is why it is used as a colourant in glass and porcelain production. The element also boosts the performance of fibre optic cables, which are required for fast internet connections. Erbium is also used in lasers in medicine. The erbium:YAG laser is superior to conventional carbon-based lasers as it generates less heat and makes treatments less painful. Due to its relatively high cost and low number of applications, the use of erbium in practice is comparatively limited.
