boribite

Boribite is a rare mineral with the chemical formula Na2Ca2B5O10(OH). It was first discovered in 1971 in the Borrowdale Volcanic Group in Cumbria, England. The mineral is named after the Borrowdale Valley where it was found. Boribite is typically found in association with other borate minerals such as sassolite and datolite. It is a sodium-calcium borate mineral that crystallizes in the monoclinic crystal system. The crystals of boribite are usually small and prismatic, often found in radiating groups or as crusts. The mineral has a hardness of 5.5 on the Mohs scale and a specific gravity of approximately 2.7. Boribite is typically colorless or white, but it can also be found in shades of yellow, brown, or gray due to impurities. It is translucent to transparent with a vitreous luster. The mineral is not commonly used in industry or jewelry due to its rarity and the difficulty in finding large, well-formed crystals. Boribite is primarily of interest to mineral collectors and researchers studying the geology of borate deposits.