Gwihabaite
Gwihabaite is a rare ammonium potassium nitrate mineral (NH4,K)(NO3). It is orthorhombic in form, colorless with a vitreous luster. It has a Mohs hardness of 5 and a specific gravity of 1.77. It is deliquescent and water soluble. The mineral is also known as nitrammite. It was first described in 1996 for an occurrence in Gcwihaba Cave (Drotsky's Caverns, type locality), Maun, North-West District, Botswana. It occurs as incrustations and efflorescences on cave surfaces formed by bacterial action on bat guano.