Boltonite is a mineral that occurs in various shades of white, gray, or pale yellow and belongs to the carbonate mineral group. It typically crystallizes in the orthorhombic crystal system and possesses a vitreous to pearly luster. The mineral was first discovered in Bolton, Massachusetts, United States, and derived its name from its type locality.
Composed primarily of calcium, magnesium, carbon, and oxygen, boltonite forms as a secondary mineral in metamorphic rocks, particularly in marble and skarn deposits. It often occurs alongside other minerals such as calcite, dolomite, phlogopite, and tremolite. With a relative hardness of approximately 4.5 on the Mohs scale, boltonite exhibits a brittle tenacity and uneven fracture.
In terms of its physical properties, boltonite has a specific gravity ranging from 2.8 to 2.9, indicating its moderate density. Its pleochroism is typically weak, and it displays biaxial positive optical characteristics. These properties allow for its identification under a microscope through the use of various analytical techniques.
While boltonite has limited economic significance, its distinctive crystal structure and appearance make it a popular collector's mineral. Its delicate coloration and rare occurrences in nature make it particularly sought after among mineral enthusiasts. Additionally, studies on boltonite can contribute to our understanding of metamorphic processes and the formation of mineral assemblages.
