What is lepidocrocite?

Lepidocrocite is a mineral composed of iron oxide hydroxide. Its chemical formula is γ-FeO(OH). It is classified as a secondary mineral, meaning it forms as a result of weathering and alteration processes on other iron-bearing minerals.

Lepidocrocite typically forms as a coating on other minerals, such as hematite or goethite, and is commonly found in iron ore deposits, bogs, and other wet environments where iron-rich minerals are exposed to oxygen and water. It often occurs in the form of fine, radiating fibers or needle-like crystals.

Lepidocrocite is often red to reddish-brown in color, but it can also appear as orange, yellow, or black. It has a Mohs hardness of 5 to 5.5, making it relatively soft compared to other minerals.

It is named after the Greek words "lepis" meaning scale and "krokis" meaning saffron, in reference to its scaly appearance and reddish color. Lepidocrocite has been found in various locations around the world, including Brazil, the United States, Sweden, Russia, and Australia.