4.6" Red-Brown Jarosite Crystal Cluster - Colorado Mine, Utah

Jarosite is the most common mineral of the alunite supergroup with a base chemical formula of KFe3+ 3(SO4)2(OH)6. The crystals are usually found as brown to amber-yellow granular crusts or coatings within cavities. The crystals are often very small: larger crystal formations are considered relatively rare. The crystals are most often found with tabular and/or pseudo-cubic structures.