Formula: Zn(SO4).7H2O
Hydrated normal sulphate, epsomite group and forms a series with it. Epitaxial mineral: muscovite (Mindat)
Specific gravity: 1.978
Hardness: 2 to 2½
Streak: White
Colour: Colourless, white, light brown, green or blue, colourless in transmitted light.

Hydrothermal environments

Goslarite is a secondary mineral in oxidised portions of zinc sulphide deposits, particularly as efflorescent crusts on mine timbers formed from the oxidation of sphalerite (Webmin, Dana, HOM). Associated minerals include epsomite, melanterite, pickeringite, chalcanthite and gypsum (HOM).


The type locality is the Rammelsberg Mine, Rammelsberg, Goslar, Lower Saxony, Germany.

At Creede, Mineral county, Colorado, USA, goslarite is the most common postmining mineral. Silky white growths, which can reach a length of over a foot, are commonly found hanging from the backs of drifts in the mines, and are made up of thousands of hairlike strands (R&M 85-5.413).

Back to Minerals