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.