What is Emmonsite?
Emmonsite is a hydrated ferric tellurite that forms pale yellow-green crusts and fine aggregates in oxidised tellurium-bearing deposits.
Mineralogy and structure
Reference formula: Fe2(TeO3)3·2H2O. Emmonsite is triclinic and contains ferric iron, tellurium and structural water. Its fine crusts and lichen-like aggregates are more common than large euhedral crystals.
Colour and appearance
Typical colours include yellow-green, pale green, yellow. The usual acicular, fibrous, botryoidal habit and vitreous, earthy lustre are useful descriptive features, but colour alone is not diagnostic.
Formation and localities
Emmonsite forms in or is associated with oxidised gold-tellurium deposits and weathering zones of telluride ores. Important documented localities include Arizona, Nevada, California and other tellurium-rich mining districts.
Collecting and care
Display only and keep labelled; tellurium-bearing minerals should not be cut, ground or treated as ornamental raw material.
Emmonsite in popular symbolism
Modern crystal guides sometimes associate Emmonsite with symbolic themes based on colour or collecting tradition. These associations are cultural interpretations, not mineralogical or medical properties.
