Solubility: Gypsum Is moderately soluble in drinking water, using a solubility of about two grams for each liter at 25°C. Apparently, gypsum displays retrograde solubility, which means its solubility decreases as h2o temperature increases – unlike most salts that turn out to be more soluble in very hot drinking water. https://www.propanraya.com/id/produk/eco-gypsum-ee-4050