Explanation

Simple chain structured hydroxide minerals. There are often mixed substances such as Mn (up to 5%) and A1. Orthorhombic crystal system. The parallel Z axis of crystal is needle shaped, columnar and longitudinal, or lamellar or scaly. The aggregates are bean shaped, kidney shaped, and stalactite shaped. The cutting surface is parallel, radial, fibrous, and also commonly in dense block or soil shape. Red brown, dark brown to black, with streaks of reddish brown. diamond to semi metallic luster. The fracture surface is uneven and brittle. It is mainly formed under exogenous conditions and is the main mineral component of limonite. It can be used as raw mineral material for ironmaking in large quantities.

Classification