Wiktionary
stone paper
n. a type of paper manufactured from calcium carbonate mixed with a high density polyethylene bonding agent
Wikipedia
Stone paper
Stone paper (also known as rock paper, paper from waste marble, mineral paper, or rich mineral paper) is a paper-like product manufactured from calcium carbonate bonded with high-density polyethylene (HDPE). It is used for stationery, leaflets, posters, books, magazines, bags, packaging, wallpaper, adhesives, tags, in-mould labels, plates, trays, containers and many other uses.