Flamite

Chemical formula: Ca₈-x(Na,K)x(SiO₄)₄-x(PO₄)x

Flamite is a rare mineral from the larnite group, a calcium silicate with sodium, potassium, and phosphate admixtures, discovered in the Hatrurim Formation in Israel.

## Characteristics Flamite is a mineral belonging to the larnite group. It occurs as small, anhedral (irregularly shaped) grains, usually not exceeding 100 micrometers in size. These grains are most commonly found as inclusions in other minerals, such as larnite. Due to its size and mode of occurrence, its visual features are difficult to observe without specialized equipment. ## Physical Properties This mineral is characterized by a hardness of 5-5.5 on the Mohs scale. Its density, calculated from crystallographic data, is 3.264 g/cm³. It is transparent and has a white streak. It does not exhibit fluorescence under ultraviolet light. ## Colors and Varieties Flamite is typically grayish to yellowish. No color or commercial varieties have been distinguished. ## History and Name The mineral's name comes from Professor Evgeny Flam, an Israeli chemist from the Hebrew University of Jerusalem, in recognition of his contribution to research on materials from the Hatrurim Formation. Flamite was approved as a new mineral by the International Mineralogical Association (IMA) in 2013. Its discovery was made in rock material from the southern part of the Hatrurim basin in Israel. ## Applications Flamite has no industrial applications. Its significance is purely scientific and collectible, especially for micromineral collectors and collectors of minerals from unique localities.

Properties

Mohs hardness: 5-5.5
Streak: white
Density: 3.264
Fracture: Irregular/Uneven
Transparency: Transparent
Crystal system: Orthorhombic

Diagnostic features

## Identification Identification of flamite is only possible using advanced laboratory methods, such as X-ray diffraction (XRD) and chemical microanalysis (EDS/WDS). In field conditions and in a typical collection, its identification is impossible due to its microscopic size and occurrence as inclusions. ## Distinguishing from Similar Minerals Flamite is visually almost impossible to distinguish from co-occurring minerals such as larnite, brownmillerite, or ye'elimite, without specialized analysis. All these minerals form similar, fine grains in the rocks of the Hatrurim Formation. ## Crystal Forms This mineral forms exclusively anhedral, irregular grains up to 100 µm in size. No well-formed crystals have been observed.

Geological environment

## Genesis Flamite forms under conditions of pyrometamorphic (contact) metamorphism at high temperatures and low pressure. It is a product of the natural combustion of bituminous rocks, which led to the transformation of sedimentary marls and limestones. This process is characteristic of the Hatrurim Formation, also known as the "Mottled Zone" or "Burnt Formation". ## Mineral Associations Flamite co-occurs with other rare minerals formed under similar conditions. It is most often accompanied by larnite, brownmillerite, ye'elimite, and minerals from the ettringite group. ## Localities The only confirmed locality of flamite in the world is its type locality – the southern part of the Hatrurim basin, in the Negev Desert in Israel.

Rarity

Very rare

For collectors

## Quality Criteria The quality of a flamite specimen is assessed solely based on the confirmation of its presence using analytical methods. Since the mineral is microscopic, its collectible value lies in the richness of the mineral association on a given rock fragment and in the precise documentation of the locality. Specimens where flamite occurs in association with other rare minerals from the Hatrurim Formation are more desirable. ## Popular Localities The only source of specimens is the Hatrurim Formation in Israel. Material for research and collections comes exclusively from this unique geological area.

Care and storage

## Cleaning Flamite specimens, typically microscopic grains within the host rock, do not require and should not undergo mechanical or chemical cleaning. Any attempts at isolation or cleaning may lead to the destruction of the delicate material. ## What to Avoid Contact with acids and other aggressive chemicals should be avoided. Due to its occurrence as fine grains, the specimen should be protected from shocks, friction, and ultrasound, which could damage the host rock. ## Storage Specimens containing flamite are best stored under stable conditions, in sealed "micromount" boxes, which protect them from dust and mechanical damage. Extreme changes in temperature and humidity should be avoided.

External references

https://www.mindat.org/min-46073.html