Answer: Limestone!
Stone paper is made of powdered limestone (about 80% calcium carbonate) derived from limestone quarries – often from waste materials. This makes it much harder to tear than paper made from trees.
It is also waterproof and – I kid you not – described by no less an authority than Wikipedia as having a “texture somewhat like that of the outer membrane of a boiled egg.” (They mean it’s smooth. But seriously, ugh.)
And though its makers tout its eco-credentials – no trees are used in its making – recycling stone paper can pose a challenge.
Photo by Scott Webb on Unsplash
