The chemical composition of mineral Cassagnaite is indicated by the formula (Ca,Mn++)4(Fe+++,Mn+++,Al)4(OH)4(V+++,Mg,Al)2(O,OH)4(Si3O10)(SiO4)2. Cassagnaite is usually found in fractures in braunite plus quartz layered mineralization, together with piemontite. Cassagnaite is commonly found from its type of locality at Cassagna mine, Val Graveglia, eastern Liguria, northern Apennines, Italy. Cassagnaite was named after the locality. Mineral Cassagnaite is also known to crystallize in the orthorhombic system of crystal formation. In optical mineralogy, this orthorhombic crystal system comprises crystals having three mutually perpendicular axes, of which all are of different lengths. Cassagnaite is usually found with distinct cleavage in one direction when viewed with the aid of polarized microscopes. Mineral Cassagnaite is also found showing golden brown color in hand sample. Most crystals of mineral Cassagnaite are found transparent appearance. Cassagnaite is also found showing brittle fracture which is generally displayed by glasses and most non-metallic minerals. Sometimes mineral Cassagnaite is also found prismatic in form with crystals shaped like slender prisms similar to tourmaline. Cassagnaite can be also found tabular in form with dimensions that are thin in one direction. Cassagnaite is also found showing vitreous or glassy luster in reflected light of polarizing microscopes. Cassagnaite is commonly found leaving nearly white streak when rubbed on white porcelain streak plate. Cassagnaite is also commonly found showing biaxial figure when evaluated between crossed nicols of petrographic polarizing microscopes. Mineral Cassagnaite is also showing 0.0100 birefringence. Cassagnaite is found to be not radioactive.