Ravatite

Chemical formula: C₁₄H₁₀

Ravatite is a rare organic mineral – a naturally occurring phenanthrene, valued by collectors for its unique origin and fluorescence.

## Characteristics Ravatite is a mineral from the group of organic compounds, consisting of the polycyclic aromatic hydrocarbon – phenanthrene (C₁₄H₁₀). It occurs as very small, colorless or white to pale yellow, tabular crystals, often forming thin coatings and crusts on rocks. Specimens are usually small, and individual crystals rarely exceed 1 mm. It is one of the few minerals of organic origin. ## Physical Properties Ravatite is very soft, with a Mohs hardness of only 1. It has a low specific gravity, around 1.1-1.2 g/cm³. Crystals exhibit a pearly luster on cleavage surfaces and a vitreous luster on other faces. It is transparent to translucent. A characteristic feature is strong, blue-violet fluorescence under ultraviolet light. ## Colors and Varieties The mineral is usually colorless, white, pale yellow, or light brown. No color or commercial varieties are distinguished. ## History and Name The mineral's name comes from the locality of Ravat in Tajikistan, where it was discovered near a burning coal seam. It was described and approved as a new mineral by the International Mineralogical Association (IMA) in 1992. Its discovery is linked to research on naturally occurring organic compounds in geothermal environments. ## Uses Due to its rarity, small crystal size, and specific formation conditions, ravatite has no industrial applications. It is solely an object of scientific and collector interest.

Properties

Mohs hardness
1
Color
Colourless to gray
Luster
Pearly
Streak
White
Density
1.11
Cleavage
{001}
Fracture
Uneven
Transparency
Transparent,Translucent
Crystal system
Monoclinic

Diagnostic features

## Identification The most important diagnostic feature of ravatite is its intense blue-violet fluorescence under ultraviolet light (both longwave and shortwave). Other features include extreme softness, low specific gravity, and occurrence as small, tabular crystals in a specific environment (near burning coal seams). ## Distinguishing from Similar Minerals It can be confused with other colorless or white secondary minerals occurring in similar environments, such as native sulfur (which is yellow and does not fluoresce blue) or salammoniac. However, the fluorescence test is crucial and allows for unambiguous differentiation of ravatite. ## Crystal Forms Ravatite crystallizes in the monoclinic system, forming thin, tabular or bladed crystals, often arranged in rosette-like or fan-shaped aggregates. It also occurs as thin coatings and crusts.

Geological environment

## Genesis Ravatite is an organic mineral, formed by the sublimation of volcanic gases or gases from underground coal fires. It crystallizes from the gas phase in lower temperature zones (below 100-150°C) in rock fractures and voids. ## Mineral Associations It co-occurs with other minerals formed under similar conditions, such as native sulfur, salammoniac, and other rare organic minerals. ## Localities The most important and type locality, from which the mineral's name originates, is Ravat in the Yagnob River valley in Tajikistan. It is also known from several other locations worldwide where underground coal fires occur, including Pennsylvania and West Virginia (USA), and Germany (Hesse, Saxony).

Rarity

Very rare

For collectors

## Quality Criteria The collector appeal of ravatite primarily depends on the abundance and visibility of crystals on the rock matrix. Specimens with clearly formed, white or colorless crystals forming dense coatings or rosette-like aggregates are most valued. Due to the small size of the crystals, specimens are often evaluated under a microscope. The intensity of fluorescence also increases the specimen's value. ## Popular Localities The most classic and sought-after specimens come from the type locality in Ravat, Tajikistan. Specimens from American localities, such as the Burnside coal mine in Pennsylvania, are also present on the collector's market.

Care and storage

## Cleaning Ravatite specimens are extremely delicate and sensitive. Any mechanical or chemical cleaning should be avoided. Only very careful dust removal with a soft brush or a photographic air blower is permissible. ## What to Avoid The mineral is very soft (Mohs hardness 1), susceptible to scratches and mechanical damage. Avoid contact with water, organic solvents, and all chemicals. It is sensitive to elevated temperatures – it can sublimate (transition from solid to gas) at temperatures above 100°C. It should be protected from direct sunlight and moisture. ## Storage Specimens should be stored under stable conditions, in closed, airtight containers (e.g., "membrane box" type or perky boxes), to protect them from dust, moisture, and physical damage. Store away from heat sources.

External references

Sources

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