Skis made of stone?

I was talking to my friend down in Disentis Switzerland, He told me that they were making skis out of stone. I was like! WHAT? No that's not F__king possible.
But I was proven wrong ones more :(

So here they are expensive like hell but they have a stone core.
You can´t say now to a stone core...




http://www.zai.ch/index.php?id=4&L=1