The Messenger of Allah ﷺ forbade plastering graves with gypsum.
حدثنا أزهر بن مروان ومحمد بن زياد قالا حدثنا عبد الوارث عن أيوب عن أبي الزبير
نهى رسول الله ﷺ عن تجصيص القبور
No references are available.
Muslim narrated it in the chapter on the prohibition of plastering graves and building over them, h: 970, from the hadith of Ayub with the same chain, with slight variation in wording.