You are looking at a phenomenon. Chalk for the black board at school, with a sponge to erase whatever mistake you made or handwriting error you weren’t too pleased with. Plüss-Staufer was founded in Switzerland in 1884. Eventually they took over Europe with opening other factories in Austria, France, Germany, Turkey, and the US. Since 1891 Plüss-Staufer developed chalk powder. The black board is now going towards extinction – chalk does not go well with iPads nor whiteboards.