2.4" Red-Brown Jarosite & Quartz Association - 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, with larger crystal formations being considered relatively rare. The crystals are most often found with tabular and/or pseudo-cubic structures.

Silicon Dioxide, also known as SiO2 or Quartz, is the second most abundant mineral in the Earth's crust. Quartz crystals generally grow in silica-rich, hot watery solutions called hydrothermal environments, at temperatures between 100°C and 450°C, and usually under very high pressure. Quartz veins are formed when open fissures are filled with hot water during the closing stages of mountains forming, and can be hundreds of millions of years old.