Zhonghuacerite-(Ce)

Chemical formula: Ba₂Ce(CO₃)₃F

Zhonghuacerite-(Ce) is a rare barium and cerium fluorocarbonate, forming small, hexagonal crystals with a vitreous or greasy luster.

## Characteristics Zhonghuacerite-(Ce) is a mineral from the carbonate group, chemically a barium and cerium fluorocarbonate. It occurs as small, hexagonal, tabular or short-prismatic crystals, rarely exceeding 1 mm in size. Crystals often form rosette-like or radial aggregates. It is a brittle mineral. ## Physical Properties The mineral has a hardness of approximately 4.5 on the Mohs scale and a significant density of about 4.75 g/cm³. The luster is vitreous, and on fracture surfaces, it can be greasy. It is transparent to translucent. ## Colors and Varieties Zhonghuacerite-(Ce) is usually colorless, white, yellowish, or pale pink. No commercial or colored varieties are distinguished. ## History and Name The mineral's name refers to its discovery location – "Zhonghua" is the Chinese name for China. The suffix -(Ce) indicates the dominant rare earth element in its composition, which is cerium. It was first described in 1981 by Zhang Peishan and Tao Kejie based on material from the Bayan Obo iron and rare earth ore mine in China. ## Uses Zhonghuacerite-(Ce) has no industrial application. It is of purely scientific and collector's interest as a rare mineral.

Properties

Mohs hardness: 4.5
Color: Yellow
Luster: Vitreous, Resinous
Streak: White
Density: 0
Cleavage: Good on {0001}
Fracture: Uneven
Transparency: Transparent
Crystal system: Trigonal

Diagnostic features

## Identification Field identification is practically impossible due to the small size of the crystals and their resemblance to other carbonates. Characteristic features include the hexagonal outline of crystals and occurrence in association with other rare earth minerals. Definitive identification requires advanced analytical methods, such as X-ray diffraction (XRD) and chemical analysis (EDS/WDS). ## Distinguishing from Similar Minerals It can be confused with other rare earth carbonates, such as Bastnäsite-(Ce), Parisite-(Ce), or Cordylite-(Ce), with which it often co-occurs. Visual differentiation is unreliable; chemical analysis showing the presence of barium and fluorine in the absence of calcium is crucial. ## Crystal Forms It forms hexagonal, tabular, or short-prismatic crystals. It often occurs as radial or rosette-like clusters and aggregates.

Geological environment

## Genesis Zhonghuacerite-(Ce) is a mineral of hydrothermal origin. It forms in carbonatites and in hydrothermal veins associated with sodium metasomatism (fenitization) processes. ## Mineral Associations It most commonly co-occurs with other rare earth minerals. In its type locality (Bayan Obo), it was found in association with Aegirine, Riebeckite, Fluorite, Baryte, Bastnäsite-(Ce), Cordylite-(Ce), Parisite-(Ce), and Huanghoite-(Ce). ## Localities The most important and type locality is the vast Bayan Obo iron and rare earth ore deposit in Inner Mongolia, China. This is practically the only locality from which well-characterized specimens of this mineral originate.

Rarity

Very rare

For collectors

## Quality Criteria The collector's appeal of a specimen depends on the size and habit of the crystals and the richness of the aggregates. Specimens with distinct, sharp crystals forming radial or rosette-like clusters on a contrasting matrix, e.g., on Aegirine, are most valued. Due to the small size of the crystals, specimens are usually micromounts. ## Popular Localities The only source of collector specimens is the Bayan Obo deposit in China.

Care and storage

## Cleaning Specimens should be cleaned only very carefully, using a soft brush to remove dust. Due to its brittleness and rarity, avoid washing in water, especially in ultrasonic cleaners. ## What to Avoid The mineral is sensitive to acids, which cause it to dissolve rapidly with the release of carbon dioxide. Avoid contact with chemicals, sudden temperature changes, and mechanical shocks. ## Storage It is recommended to store specimens in stable conditions, in closed display boxes, away from dust and direct sunlight. It is best to protect it from shocks and contact with harder minerals.