The chemical formula of mineral Natrojarosite is indicated by NaFe3(SO4)2(OH)6 or Sodium Iron Sulfate Hydroxide. This Natrojarosite is actually a Sulfate mineral. It is most commonly used as a mineral specimen. Mineral Natrojarosite is most commonly found exhibiting nice and interesting microscope appearance when viewed with the aid of petrographic polarizing light microscope used in the field of optical mineralogy. However, Natrojarosite is somewhat a rare sulfate mineral. Natrojarosite is also known in optical mineralogy to be closely related to mineral Jarosite. Jarosite is actually isostructural with Natrojarosite. In the filed of optical mineralogy, isostructural means that the two minerals have the same crystal structure but with different chemistries. In the case of these two minerals, Jarosite contains potassium instead of sodium which is present in Natrojarosite. Natro is derived from the Latin word natrium for sodium from where the element got its symbol Na. the two minerals are actually difficult to distinguish without a chemical test. It has been also known that these two minerals are isostructural with the mineral Alunite.
The symmetry of the mineral Natrojarosite is actually the same as that of the Tourmaline Group. The crystals of mineral Natrojarosite however do not form prismatic crystals like those of the typical tourmaline minerals. The crystals of the Natrojarosite are more flattened and resemble nearly cubic rhombohedrons. In the field of optical mineralogy, rhombohedrons are actually a combination of two trigonal pyramids. Natrojarosite crystals are unfortunately scarce. Natrojarosite mineral crystals are most commonly found transparent to translucent in appearance. Natrojarosite is known to crystallize in the trigonal system of crystal formation. The crystal habit of mineral Natrojarosite as described in the field of optical mineralogy commonly includes tabular to flattened rhombohedral looking crystals. In optical mineralogy, rhombohedrons are actually a combination of two trigonal pyramids. Natrojarosite crystals are actually scarce and are more commonly found as earthy masses, films or crusts, botryoidal and granular.
Mineral Natrojarosite is most commonly found colored yellow, orange, or brown and can be seen more splendidly exhibited when viewed with the aid of petrographic polarizing light microscopes for mineralogists. Natrojarosite is also most often found exhibiting vitreous luster when viewed in reflected light of petrographic polarizing microscope for mineralogists. Natrojarosite is also commonly found exhibiting a good cleavage in one direction but can only be seen in the larger crystals when closely evaluated with the aid of petrographic polarizing light microscopes. When viewed closely under the polarized microscopes for mineralogists, it is also most commonly found showing uneven fracture. The hardness measure of the mineral Natrojarosite when it is evaluated using the Mohs scale method is usually ranging from 3 to 4. When specimen of Natrojarosite is rubbed on a white porcelain streak plate, it is most commonly found leaving a yellow streak. The specific gravity measure of the mineral Natrojarosite is most commonly found ranging from 3.1 grams per cubic centimeters to 3.3 grams per cubic centimeters, which is slightly heavy for translucent minerals, but hard to obtain from crusts. The best field indicators of mineral Natrojarosite include hardness, color, crystal habit, and association. Natrojarosite is also most commonly found associated with other interesting minerals such as barite, hematite, limonite, goethite, and other iron minerals. Natrojarosite notably occurs are several localities including Black Hills, South Dakota and Soda Springs Valley, Nevada, USA as well as in Chili, Russia, Mexico, and Greece.
