Cubothioplumbite

Chemical formula: [Pb₂+₄(OH)₄]Pb₂+(S₆+O₃S₂-)₃

An extremely rare, newly discovered lead mineral, distinguished by its unique crystal structure and chemical composition, found so far in only one location worldwide.

## Characteristics Kubotioplumbite is a lead mineral with a complex chemical composition, containing both sulfate and sulfide in its structure. It forms very small, cubic crystals, reaching sizes up to 0.1 mm. They usually occur as irregular aggregates or thin coatings on other minerals. Due to the microscopic size of the crystals, its visual features are difficult to observe without specialized equipment. ## Physical Properties Kubotioplumbite crystals exhibit a luster ranging from vitreous to adamantine. They are transparent to translucent. Hardness and density have not been precisely measured due to the small amount of available material; however, the density calculated based on the formula and unit cell parameters is 6.43 g/cm³. ## Colors and Varieties This mineral is colorless. No colored or commercial varieties are known. ## History and Name Kubotioplumbite was officially recognized as a new mineral by the International Mineralogical Association (IMA) in 2023 (IMA2023-012). Its name refers to the cubic symmetry of its crystals and its chemical composition, containing sulfur (Greek *theîon*) and lead (Latin *plumbum*). It was discovered in the Redmond mine in Haywood County, North Carolina, USA. ## Applications Kubotioplumbite has no industrial applications. Its significance is purely scientific and collectible, as a unique and newly discovered mineral species.

Properties

Luster: Vitreous to Adamantine
Streak: White
Density: 6.43
Transparency: Transparent to Translucent
Crystal system: Cubic

Diagnostic features

## Identification Identification of kubotioplumbite is impossible without advanced analytical methods, such as Raman spectroscopy or X-ray diffraction (XRD). Under collecting conditions, identification relies solely on trust in the label and the reputation of the source from which the specimen originates, especially since it comes from a single, specific location. ## Distinguishing from Similar Minerals It can be confused with other colorless or white secondary lead minerals, such as cerussite, anglesite, or lanarkite, which often co-occur with it. Visual differentiation is practically impossible due to the microscopic size of the crystals. Only laboratory analysis provides certainty. ## Crystal Forms Kubotioplumbite forms isometric, cubic crystals, but due to their small size (up to 0.1 mm), it is most often observed as irregular aggregates and coatings.

Geological environment

## Genesis It is a secondary mineral, forming in the oxidation zone of lead ore deposits. It forms as a result of galena weathering in the presence of sulfate-rich solutions. In the type locality (Redmond mine), it formed in voids within quartz rock. ## Mineral Associations Kubotioplumbite co-occurs with other secondary lead minerals. In the type locality, it was found in association with anglesite, lanarkite, pyromorphite, galena, sphalerite, chalcopyrite, and quartz. ## Localities The only confirmed occurrence of kubotioplumbite in the world is the Redmond mine, located in Haywood County, North Carolina, USA. This is its type locality.

Rarity

Extremely rare

For collectors

## Quality Criteria The quality of a kubotioplumbite specimen primarily depends on the confirmation of its identity by a reliable source. Since the crystals are microscopic, the most important criterion is the richness of the aggregates and their association with well-formed crystals of co-occurring minerals, which enhance the overall aesthetic of the specimen. Every authentic specimen is valuable from a scientific perspective. ## Popular Localities The only source of specimens is the Redmond mine in North Carolina, USA. This locality is known for the occurrence of many rare secondary minerals.

Care and storage

## Cleaning Due to its extreme rarity, small crystal size, and delicacy, specimens containing kubotioplumbite should not be cleaned mechanically or chemically. Any attempts at cleaning may irreversibly damage the mineral. It is best to leave it in its untouched state. ## What to Avoid Avoid contact with all chemicals, acids, and even water. Protect it from vibrations, ultrasound, temperature changes, and humidity. Do not touch it or expose it to direct sunlight. ## Storage Specimens should be stored only in specialized, sealed "micromount" boxes, away from dust, light, and temperature fluctuations. The safest way is to store it in the original container in which it was acquired.

Sources

IMA Mineral List (CNMNC)