Goslarite

Goslarite is a zinc sulfate mineral with the chemical formula ZnSO₄·7H₂O. It is commonly found as a secondary mineral in the oxidized zones of zinc-bearing ore deposits.

Properties:

Goslarite is a hydrated sulfate, meaning it contains water molecules within its crystal structure. It is typically found as white, pinkish, or colorless orthorhombic crystals, often forming crusts, coatings, or fibrous aggregates. The mineral is relatively soft, with a Mohs hardness of 2 to 2.5, and has a vitreous luster. Its streak is white. Goslarite is water-soluble and has a characteristic metallic, astringent taste. Due to its solubility, it can be unstable in humid conditions and may dehydrate to form other zinc sulfates.

Occurrence:

Goslarite is a relatively common secondary mineral, found in association with other zinc minerals such as sphalerite, galena, and pyrite. It is often found in mine workings and caves where zinc-rich minerals have been subjected to weathering and oxidation. Notable occurrences include Germany (where it was first described), the United States, and various other countries worldwide.

Uses:

Goslarite itself does not have significant commercial uses. However, its presence can be an indicator of zinc-rich ore deposits and can be a byproduct of mining operations. Zinc sulfate, the anhydrous form of goslarite, has various applications, including as a micronutrient in fertilizers, as a mordant in dyeing, and in pharmaceutical preparations.

Distinguishing Characteristics:

Goslarite can be distinguished from other similar-looking minerals by its association with zinc-bearing deposits, its solubility in water, its astringent taste, and its characteristic crystal habit. X-ray diffraction and chemical analysis can provide definitive identification.