Bellbergite is a relatively rare mineral that belongs to the borate group. Its chemical composition is categorized as a hydrated calcium borate sulfate, with the chemical formula Ca4(SO4)(B6O7)(OH)6·(H2O). This mineral was initially discovered in Bellberg, Sweden, hence the name "bellbergite."
Bellbergite typically forms as small, prismatic crystals that are commonly colorless or white. It has a vitreous to silky luster and has a white streak. It frequently occurs in association with other borate minerals such as boracite.
In terms of its physical properties, bellbergite has a hardness of approximately 3.5 on the Mohs scale, indicating a relatively low level of hardness. It is also characterized by its cleavage, which is described as perfect in two different directions. Additionally, bellbergite is soluble in dilute acids.
Although the exact geological formation processes of bellbergite remain somewhat unclear, it has been found in marine sedimentary deposits, often in association with evaporite minerals. These deposits are usually found in arid or semi-arid regions.
Bellbergite holds a relatively limited economic significance, primarily due to its scarcity and lack of notable industrial uses. However, due to its unique crystal structure and occurrence in various geological environments, it is valued by mineral enthusiasts and collectors. Its aesthetic qualities, coupled with its rarity, contribute to its desirability within the mineral collecting community.
