Slavíkite

Slavíkite is a rare sulfate mineral with the chemical formula Mg₄Fe₃(SO₄)₆(OH)₁₀·28H₂O. It is characterized as a hydrous magnesium iron sulfate hydroxide. Slavíkite typically occurs as earthy or powdery aggregates, often forming crusts or coatings.

It is found in association with other secondary sulfate minerals in arid or semi-arid environments, often as a product of the weathering of sulfide minerals or volcanic fumaroles.

Slavíkite is usually yellow to yellowish-brown in color. Its crystal structure is poorly defined due to its fine-grained nature. Identification is generally performed using X-ray diffraction and chemical analysis.

The mineral is named after František Slavík (1876-1957), a Czech mineralogist and professor at Charles University in Prague.