Gypsum Caves: Gypsum caves, also called gypsum karst caves, type in the dissolution of gypsum by groundwater. As slightly acidic h2o percolates via gypsum-rich bedrock, it little by little dissolves the gypsum, developing underground voids and passages. Nossos produtos estão em conformidade com as Normas Técnicas ABNT NBR Drywall e https://www.propanraya.com/id/produk/eco-gypsum-ee-4050