cobalt chloride

chemical compound

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June 24, 2026

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Cobalt chloride, specifically cobaltous chloride (CoCl₂), is a chemical compound of cobalt. It is known for its color-changing properties, being blue when dehydrated and turning red in the presence of moisture, which makes it useful as a humidity indicator.12

Cobalt itself is a ferromagnetic metal and a chemical element. Historically, cobalt compounds have been used for centuries to create blue colors in glazes and ceramics. Cobalt is an essential trace element for ruminants and is a component of vitamin B₁₂ in humans. While cobalt ores are not typically mined solely for cobalt, it is often recovered as a byproduct of mining other metals like iron, nickel, and copper.3

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blood doping
Erythropoietin
…production include the administration of cobalt chloride, which enhances transcription of the erythropoietin gene. Because this practice involves manipulation of a genetic element, it is considered by some to be a form of gene doping.
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…production include the administration of cobalt chloride, which enhances transcription of the erythropoietin gene. Because this practice involves manipulation of a genetic element, it is considered by some to be a form of gene doping.
Read More

coordination compound
History of coordination compounds
…1798 that ammoniacal solutions of cobalt chloride, CoCl₃, develop a brownish mahogany color. He failed to follow up on his discovery, however. It remained for others to isolate orange crystals with the composition CoCl₃ ∙ 6NH₃, the correct formulation of which is recognized to be [Co(NH₃)₆]Cl₃; this shows that the…
Read More
…1798 that ammoniacal solutions of cobalt chloride, CoCl₃, develop a brownish mahogany color. He failed to follow up on his discovery, however. It remained for others to isolate orange crystals with the composition CoCl₃ ∙ 6NH₃, the correct formulation of which is recognized to be [Co(NH₃)₆]Cl₃; this shows that the…
Read More