Iraqite-(La)
Chemical formula: KCa<sub>2</sub>(La,Ce<sup>3+</sup>,Th<sup>4+</sup>)Si<sub>8</sub>O<sub>20</sub>
A rare, radioactive silicate of potassium, calcium, and lanthanides, discovered in Iraq and occurring as pale green aggregates.
Description
## Characteristics Iraqite-(La) is a very rare mineral from the ekanite group, belonging to the silicate class. It forms irregular, anhedral grains and massive aggregates, usually embedded in the host rock. No well-formed crystals of this mineral are known. Its most characteristic visual feature is its pale green color. ## Physical Properties This mineral is translucent and exhibits a vitreous to slightly greasy luster. Its density is approximately 3.27 g/cm³. Due to the presence of thorium in its chemical composition, iraqite-(La) is a radioactive mineral. Its hardness has not been precisely determined. ## Colors and Varieties Iraqite-(La) occurs exclusively in pale green shades. No color varieties or commercial varieties have been distinguished. ## History and Name The mineral's name comes from its country of discovery - Iraq. It was first described in 1977 by a team of mineralogists (Livingstone, Atkin, Hutchison, Al-Hermezi). The suffix "-(La)" was added in 1987 to indicate that lanthanum is the dominant rare earth element in its structure, in accordance with mineral nomenclature rules. ## Uses Due to its extreme rarity and small occurrence sizes, iraqite-(La) has no industrial applications. It is solely an object of scientific interest and a valuable acquisition for specialized collectors of rare minerals.
Diagnostic features
## Identification The key diagnostic feature of iraqite-(La) is its radioactivity, easily detectable with a Geiger counter. Other helpful identification features include its pale green color, vitreous to greasy luster, and co-occurrence with characteristic minerals such as aegirine and microcline. However, definitive confirmation requires advanced chemical and X-ray analyses. ## Distinguishing from Similar Minerals It can be confused with other pale green silicates. However, the combination of radioactivity, specific occurrence environment (veins in altered basic rocks), and extreme rarity limited to one location in the world makes misidentification unlikely. ## Crystal Forms This mineral occurs as anhedral (irregular) grains and aggregates, forming massive masses within the rock. No well-formed, euhedral crystals have been observed.
Geological environment
## Genesis Iraqite-(La) forms under hydrothermal or metasomatic conditions. Its only known locality is in quartz-aegirine-feldspar veins cutting altered, basic igneous rocks. ## Mineral Associations This mineral occurs in association with aegirine, quartz, microcline, titanite, and lorenzenite. ## Localities The only confirmed locality of iraqite-(La) in the world is its type locality - Shakhi-Rash mountain in As-Sulaymaniyah province, Iraq.
Rarity
Extremely rare
Collector aspects
## Quality Criteria Due to its extreme rarity, any authentic specimen of iraqite-(La) is extremely valuable. The collector's value is primarily determined by the abundance of the mineral in the host rock (matrix) and the presence of well-formed associated minerals, such as aegirine. Specimens are usually very small, often in the form of micromounts. ## Popular Localities The only specimens available on the collector's market come from the type locality in Iraq.
Care and storage
## Cleaning Specimens should only be dry-cleaned, using a soft brush to remove dust. Wet cleaning should be avoided to prevent the spread of potentially radioactive dust. ## What to Avoid As a radioactive mineral, it requires special care. Any activities that could lead to dust formation (grinding, crushing, scratching) should be avoided. Hands should be washed after any contact with the specimen. It should not be stored in places where people spend a lot of time, especially bedrooms or offices. It should be protected from high temperatures and chemicals. ## Storage It is recommended to store specimens in separate, sealed, and clearly labeled containers, preferably with radiation shielding (e.g., lead-lined). They should be kept in a well-ventilated room, away from other minerals that could be damaged (discolored) by radiation.