Holmium-doped yttrium aluminium garnet is a laser medium: Holmium quasi-two level laser (1994). It is claimed that radioactive holmium 166 can be used to treat arthritis: Composition And Method Of Treatment Of Arthritis And Related Diseases With Holmium-166 Radionuclides (1991).
Glass containing holmium oxide is used as a calibration standard for optical spectrometers: Hyperspectral Imaging Spectrometer Spectral Calibration (2000).
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All patent information has been obtained from Espacenet (European Patent Office).