Shilonite

Shilonite is a naturally occurring mineral that belongs to the phosphate group. Its chemical formula is typically represented as (Mn,Fe)2(PO4)OH. Shilonite is characterized by its monoclinic crystal structure. The mineral is often found in association with other manganese and iron phosphates, commonly occurring in hydrothermal veins and pegmatites.

The color of Shilonite can vary, but it is frequently observed in shades of brown, reddish-brown, or yellowish-brown. It typically exhibits a dull to vitreous luster. The mineral is relatively soft, with a Mohs hardness of around 4 to 4.5. It is also known for its specific gravity, which ranges between 3.0 and 3.3.

Shilonite was first described in 1960 and named in honor of the Shilo mine in southwestern Colorado, United States, where it was discovered. While not a commercially significant mineral, it is of interest to mineralogists and collectors due to its unique composition and occurrence. Its presence can provide clues about the geological conditions under which it formed.