there from the sustainable luxury brand now to from munich sebastiaan teases the footwear brands founder his family has been in the shoe business for six generations but even for him working with stone this news. is one of them if you want it's hundreds of millions of years old all natural and each pair is unique because technically speaking it isn't superior to leather because some of the shoes are a bit less robust so you shouldn't wear them in siberia at minus forty degrees celsius but they're perfect for normal day to day purposes. the process of making stone flexible enough for shoe making starts with huge blocks of marble or slate using a special technique very thin slabs or sawn off which are then glued onto a flexible material. the method was invented by berlin based company rockslide which collaborates with sebastien teams. to fix the beauty of the spine of the heisman i think the stone becomes flexible if you make it very very thin we're talking less than one millimeter thick and then combine it with something stabilizing. the stone is then exposed to heat and cold alternately