Tag Archives: Kornerupine

Natural Kornerupine rough

Kornerupine is a rare boro-silicate mineral with the formula (Mg, Fe²⁺)₄(Al, Fe³⁺)₆(SiO₄, BO₄)₅(O, OH)₂. It has a specific gravity of 3.3 to 3.34 and Colours such as Colorless, white, grey, greenish, bluish, brown, black. Some Stones show strong Pleochroism such as colorless to green, colorless, pale brownish yellow, pale yellowish green, pale brownish green and green. The […]