andreaudite

Andreaudite is a rare mineral species that is a member of the amphibole group. It was first described in 2002 and is named in honor of Andrea and Roland Audette. The type locality for andreaudite is the Cross River pegmatite in the Kennebec River valley, Oxford County, Maine, USA.

Andreaudite has the chemical formula Ca2(Mg,Fe)5Si8O22(OH)2. It is characterized by its monoclinic crystal system and its prismatic habit. The mineral typically appears as prismatic crystals that are often elongated along the c-axis. Andreaudite can range in color from white to pale green or gray, and it typically has a vitreous to silky luster. Its hardness on the Mohs scale is around 5.5 to 6, and it has a specific gravity of approximately 3.1.

This mineral is found in association with other minerals commonly found in granitic pegmatites. Its discovery in Maine adds to the diversity of amphibole minerals known to science. Andreaudite is not of significant economic importance, but it is of interest to mineralogists and collectors due to its rarity and its contribution to understanding mineral diversity within the amphibole supergroup. Further research may reveal more about its geological formation and occurrence in other locations.