Erythrite
“Cobalt bloom in raspberry pink”
Erythrite is a hydrated cobalt arsenate mineral with a vivid crimson to raspberry-pink color that earned it the prospector's nickname 'cobalt bloom.' Its bright pink weathering crusts and crystal coatings on rock surfaces have been used for centuries as a visual guide to finding cobalt and associated mineral deposits.
cobalt arsenate hydrate (Co₃(AsO₄)₂·8H₂O)
Cobalt (Ontario, Canada), Bou Azzer (Morocco), Schneeberg (Germany), Leogang (Austria), Sara Kreek (Suriname)
1.5-2.5
The town of Cobalt, Ontario was named because of the abundant erythrite (cobalt bloom) that prospectors noticed while searching for silver — the pink mineral literally put the town on the map.
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Why was erythrite historically important to mining prospectors?
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