Szmikite
Chemical formula: Mn<sup>2+</sup>S<sup>6+</sup>O<sub>4</sub>·H<sub>2</sub>O
A rare manganese sulfate, forming pinkish, granular coatings and crusts in humid mine environments.
Properties
- Mohs hardness
- 1.5
- Luster
- Vitreous
- Streak
- White
- Density
- 3.15
- Cleavage
- Perfect on {101}
- Transparency
- Translucent
- Crystal system
- Monoclinic
Diagnostic features
## Identification Key diagnostic features of szmikite include its pinkish color, occurrence as coatings and crusts in mine environments, low hardness, and strong reaction to moisture (solubility). It often co-occurs with other manganese minerals. ## Distinguishing from Similar Minerals Szmikite can be confused with other pink secondary minerals. It is distinguished from rhodochrosite by its significantly lower hardness and lack of reaction with hydrochloric acid. Distinguishing it from other hydrated manganese sulfates, such as ilesite (MnSO₄·4H₂O) or jokokuite (MnSO₄·5H₂O), is very difficult without advanced chemical analysis (XRD), although they often form crystals with a different habit. ## Crystal Forms Szmikite crystals are rare and most often microscopic, with an acicular or bladed habit. It usually forms fibrous, radial, granular aggregates, as well as coatings, crusts, reniform forms, and small stalactites.
Geological environment
## Genesis Szmikite is a secondary mineral, forming under low temperature and pressure conditions. It forms as a product of weathering and oxidation of primary sulfides (e.g., pyrite, chalcopyrite) and manganese minerals (such as rhodochrosite or alabandite) in the presence of moisture. It is a typical "post-mining" mineral, forming on the walls of old mine workings due to the circulation of water and air. ## Mineral Associations It most often co-occurs with minerals from which it forms or which crystallize under similar conditions. These include: gypsum, epsomite, melanterite, rhodochrosite, pyrite, as well as various manganese oxides and hydroxides (so-called "psilomelane"). ## Localities The most important and classic localities for szmikite are its discovery site - Baia Sprie in Romania, as well as Idrija in Slovenia, and Gelnica and Smolník in Slovakia. It also occurs in the Inakuraishi mine in Hokkaido, Japan, and in several locations in Germany (e.g., in the Harz Mountains).
Rarity
Rare
For collectors
## Quality Criteria The most prized szmikite specimens are those from classic, historical localities, especially from the type locality in Romania. The value of a specimen is enhanced by the intensity of its pink color, a large surface covered by the mineral, and the possible occurrence in rarer forms, such as small stalactites. Due to the nature of the mineral, the presence of well-formed crystals, even microscopic ones, is highly desirable. ## Popular Localities For specialized collectors, specimens from Baia Sprie (Romania) and Idrija (Slovenia) are most sought after. Material from these locations is considered classic and has the greatest historical value.
Care and storage
## Cleaning Szmikite specimens should only be cleaned dry. To remove dust and loose debris, a soft brush (e.g., a makeup brush) can be used, or debris can be carefully blown off with compressed air from a safe distance. ## What to Avoid Contact with water and all liquids must be strictly avoided, as szmikite is soluble in it. Even high humidity can cause damage, dissolution, or transformation into other minerals. It should be protected from impacts and scratches due to its low hardness. ## Storage Szmikite requires storage in dry conditions. The best solution is a sealed, airtight box (e.g., a "perky box") with the addition of a desiccant, such as silica gel. The specimen should be isolated from other minerals that could mechanically damage it.