very special they're made of so called london marble which was mined in this area for centuries axel becker is an expert and takes me to a former quarry millions of years ago this was a reef in the ocean the continental drift carried it north along with fossilized sea creatures and sediments. and here you can see this is a coral. and this is a sea shell. put that on it after. 380000000 years ago our continent was on the equator then the continents moved and where we're standing now was 20 degrees south of the equator and on this long journey away from the equator tectonic cracks developed. there was pressure here you see these regular structures that the stone was under a lot of tectonic stress and then fused together again through cement and they would have to go back and i'm not but when did people start mining in marble so there are some of the 1st records are from 5099 we're very proud we can say it was still the 16th century. and that was the start of the barong era when marvel became popular rule there was a demand for large colorful structures that appeal to the sense of the business