Gypsum Caves: Gypsum Caves, also known as gypsum karst caves, sort from the dissolution of gypsum by groundwater. As slightly acidic drinking water percolates by way of gypsum-prosperous bedrock, it steadily dissolves the gypsum, building underground voids and passages. Nossos produtos estão em conformidade com as Normas Técnicas ABNT NBR https://www.propanraya.com/id/produk/eco-gypsum-ee-4050