Dravertite
Chemical formula: Cu<sup>2+</sup>Mg(S<sup>6+</sup>O<sub>4</sub>)<sub>2</sub>
Drawertite is a rare copper and magnesium sulfate, forming blue, tabular crystals, discovered in Russia.
Properties
- Mohs hardness
- 2
- Luster
- Vitreous
- Streak
- White
- Density
- 2.81
- Cleavage
- Perfect on {0001}
- Fracture
- Micaceous
- Transparency
- Transparent
- Crystal system
- Trigonal
Diagnostic features
## Identification Identification of drawertite is based on its characteristic appearance – small, light blue, tabular crystals with a hexagonal outline. The key is its occurrence in volcanic fumaroles. Due to the microscopic size of the crystals, definitive identification requires advanced analytical methods such as Raman spectroscopy or chemical analysis (EDS). ## Distinguishing from Similar Minerals Drawertite can be confused with other blue secondary copper sulfates, such as chalcanthite or ktenasite. Distinguishing it from these minerals in the field is practically impossible without specialized equipment. Crystal shape (thin tablets) and mineral associations can be helpful clues. ## Crystal Forms The mineral forms thin, tabular crystals with a hexagonal outline, often gathered in irregular aggregates and crusts.
Geological environment
## Genesis Drawertite is a mineral of volcanic origin, formed by sublimation from volcanic gases in active fumaroles. It crystallizes in an environment rich in sulfur, copper, and magnesium at a temperature of approximately 120-150°C. ## Mineral Associations This mineral coexists with other sulfates and fumarolic minerals, such as gypsum, chalcanthite, belloite, jarosite, hematite, as well as rare minerals like wulfenite, anglesite, kamchatkite, alarsite, atlasovite, avdoninite, eriocalcite, and tenorite. ## Localities The only confirmed locality for drawertite worldwide is its type locality – the Yadovita fumarole on Tolbachik volcano (Kamchatka, Far Eastern Federal District, Russia).
Rarity
Very rare
For collectors
## Quality Criteria The quality of drawertite specimens is primarily assessed based on the richness and abundance of crystals on the rock matrix. Since the crystals are microscopic, their quantity and visibility in an aggregate are most important. Well-formed, individual crystals, even if small, are more valued. A contrasting rock matrix also enhances the visual appeal of the specimen. ## Popular Localities The only source of drawertite specimens is the Tolbachik volcano in Kamchatka, Russia. All specimens available on the collector's market originate from this single location.
Care and storage
## Cleaning Drawertite specimens are extremely delicate and sensitive. Any mechanical cleaning should be avoided. If absolutely necessary, compressed air can be used from a safe distance to remove loose dust particles. ## What to Avoid The mineral is likely soluble in water and acids. Contact with any liquids must be strictly avoided. It is very soft and brittle, so it must be protected from any physical contact, shocks, and vibrations. High temperatures should also be avoided. ## Storage Drawertite specimens should only be stored in specialized micromount boxes, which protect them from mechanical damage, dust, and moisture. They should be kept under stable room conditions.