Wayneburnhamite
Chemical formula: Pb<sup>2+</sup><sub>9</sub>Ca<sub>6</sub>(Si<sub>2</sub>O<sub>7</sub>)<sub>3</sub>(SiO<sub>4</sub>)<sub>3</sub>
Wayneburnhamite is a rare lead-calcium silicate, forming colorless, hexagonal crystals with a vitreous luster.
Properties
- Mohs hardness
- 5
- Luster
- Vitreous
- Streak
- White
- Density
- 6.56
- Cleavage
- None
- Fracture
- Uneven
- Transparency
- Transparent
- Crystal system
- Hexagonal
Diagnostic features
## Identification Wayneburnhamite is identified by its characteristic crystal form – small, colorless, hexagonal tablets. Key features also include high density, vitreous luster, and co-occurrence with other rare lead minerals in a specific geological environment. Final identification requires advanced analytical methods, such as X-ray diffraction (XRD) and chemical analysis (EDS). ## Distinguishing from similar minerals It can be confused with other colorless minerals occurring in the same paragenesis, such as cerussite, anglesite, or quartz. It is distinguished by its hexagonal crystallographic system (cerussite is orthorhombic), lack of reaction with hydrochloric acid (unlike cerussite), and specific chemical composition. ## Crystal forms It forms well-developed, single crystals with a tabular or short-prismatic habit, exhibiting a hexagonal outline. Crystals are usually small, reaching up to 1 mm.
Geological environment
## Genesis Wayneburnhamite forms in the oxidation zones of polymetallic deposits, in metamorphic rocks (skarns) formed at the contact of quartz monzonite intrusion with carbonate sedimentary rocks (marbles). It is a product of high-temperature hydrothermal processes. ## Mineral associations This mineral co-occurs with a number of other, often rare minerals. In its type locality, it was found in association with cerussite, fluorapatite, quartz, mimetite, willemite, chalcopyrite, galena, sphalerite, iron oxides, and other lead silicates such as alamosite and esperite. ## Localities The only confirmed occurrence of wayneburnhamite in the world is its type locality – the Blue Bell mine, located in the Baker district, San Bernardino County, California, USA.
Rarity
Extremely rare
For collectors
## Quality criteria As a "micromount" mineral, its collector value primarily depends on the quality and size of the crystals. The most prized specimens are those with sharply defined, transparent, well-formed crystals that are clearly exposed on the rock matrix. The richness of association with other rare minerals is also important. ## Popular localities The Blue Bell mine in California is the sole source of specimens, making it an extremely desirable locality for collectors specializing in rare and systematic minerals.
Care and storage
## Cleaning Due to the extreme rarity and small size of the crystals, mechanical cleaning is not recommended. If absolutely necessary, compressed air can be used to remove loose dust particles. Avoid contact with water and chemicals. ## What to avoid Avoid contact with acids and other chemicals that may damage the mineral. Due to its low hardness, it is susceptible to scratches. Samples should be protected from shocks and impacts. ## Storage Wayneburnhamite specimens should be stored in specialized, sealed "micromount" boxes that protect them from dust, moisture, and mechanical damage. Avoid exposure to extreme temperature changes.