Holmium, with the chemical symbol Ho and atomic number 67, was independently discovered in 1878 by Swiss chemists Marc Delafontaine and Jacques-Louis Soret, along with Swedish chemist Per Teodor Cleve. It was isolated from the mineral erbium oxide and is named after the Latin term for Stockholm, "Holmia."

On Earth, holmium is not particularly abundant, constituting approximately 0.00002% of the Earth's crust. Despite its rarity, it finds fascinating applications in medicine and technology. Holmium is utilized in certain laser devices, particularly in surgery for the precise removal of tissues. Its ability to absorb infrared light and convert it into visible light makes it extremely useful in optical technology.

The production route of holmium begins with extraction from ores containing it, such as monazite and gadolinite. The isolation involves complex chemical processes, including extraction and precise fractionation.

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