Carboferriphoxite

Chemical formula: [(N³⁻H₄)K(H₂CO₃)][Fe³⁺(HPO₄)(H₂PO₄)((C₂)⁶⁺O₄)]

Carboferriphoxite is an extremely rare organic mineral, a hydrated iron, potassium, and ammonium phosphate-oxalate, found in the Rowley Mine in Arizona.

## Characteristics Carboferriphoxite is an organic mineral with a complex chemical composition, containing ammonium, potassium, and iron ions, as well as phosphate and oxalate groups. It forms colorless, transparent crystals with a bladed or tabular habit, occurring in small aggregates. Due to its extreme rarity and small crystal size, it is primarily of interest in scientific circles. ## Physical Properties This mineral is very soft, with a Mohs hardness of approximately 2. It is also very light, with a density of 2.14 g/cm³. It exhibits a vitreous luster and is completely transparent. It has two good cleavage planes, and its fracture is splintery. ## Colors and Varieties Carboferriphoxite is colorless. No colored varieties or trade names are known. ## History and Name The mineral's name refers to its chemical composition: "carbo" refers to the presence of carbonate and oxalate, "ferri" to ferric iron, and "phox" to the presence of phosphates. It was described as a new mineral species based on material from the Rowley Mine in Arizona, USA. ## Uses Carboferriphoxite has no industrial applications. Its significance is purely scientific and collectible, although due to its rarity and microscopic size, it rarely enters private collections.

Properties

Mohs hardness
2-0
Color
colorless
Luster
Vitreous
Streak
white
Density
2.14
Cleavage
two good cleavages (probably {100} and {001}).
Fracture
Splintery
Transparency
Transparent
Crystal system
Triclinic

Diagnostic features

## Identification Identifying carboferriphoxite under amateur conditions is practically impossible. Identification requires advanced analytical methods, such as X-ray diffraction (XRD) and chemical spectroscopy (EDS/WDS), due to its specific composition and occurrence as microscopic crystals. Its colorless nature, low hardness, and specific locality are the only, very general, clues. ## Distinguishing from Similar Minerals It can be confused with other secondary, colorless phosphate or sulfate minerals found in similar environments, such as gypsum or other rare phosphates. Definitive distinction is only possible through laboratory analysis. ## Crystal Forms Crystals are very small, usually bladed or thin-tabular. They occur as single, dispersed crystals or small, loose aggregates on the surface of other minerals.

Geological environment

## Genesis Carboferriphoxite is a secondary mineral, crystallizing under very specific conditions. It forms in the oxidation zones of polymetallic deposits in arid climates, as a result of reactions between phosphate-rich solutions (derived from the decomposition of bat guano) and iron-bearing ore minerals. ## Mineral Associations In its type locality (Rowley Mine), it co-occurs with other rare secondary minerals such as phosphosiderite, strengite, wavellite, as well as quartz and limonite. ## Localities The only confirmed and described occurrence of carboferriphoxite in the world is its type locality: the Rowley Mine, in Maricopa County, Arizona, USA.

Rarity

Extremely rare

For collectors

## Quality Criteria The quality of a carboferriphoxite specimen is determined almost exclusively by its existence and identifiability. The most highly valued specimens would be those with the largest possible, well-formed, and undamaged crystals, clearly visible against the host rock. Due to the microscopic nature of the mineral, the quality of photographic and analytical documentation confirming its identity is crucial. ## Popular Localities The only source of specimens is the Rowley Mine in Arizona. Material from this locality is extremely difficult to acquire and primarily goes to research institutions and specialized systematic collections.

Care and storage

## Cleaning Specimens of this mineral are extremely delicate and potentially water-soluble. Mechanical cleaning or the use of liquids is absolutely inadvisable. If necessary, compressed air can be used from a safe distance to remove dust. ## What to Avoid Avoid contact with water, chemicals, and sudden temperature changes. Due to its very low hardness, it is susceptible to scratches and mechanical damage with the slightest touch. ## Storage Carboferriphoxite specimens should be stored exclusively in specialized, sealed "micromount" containers, protecting them from dust, moisture, and physical damage. Avoid exposure to light and humidity changes.

External references

Sources

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