Gypsum Caves: Gypsum caves, often called gypsum karst caves, variety with the dissolution of gypsum by groundwater. As somewhat acidic h2o percolates by means of gypsum-rich bedrock, it steadily dissolves the gypsum, building underground voids and passages. Soil h2o potential checking: a gypsum block could be inserted to the soil, https://www.propanraya.com/id/produk/eco-gypsum-ee-4050