In the year 2008 by a rock dealer in Idar Oberstein an intensively yellow-black colored, nicely banded material was offered to me. This material smells as rough rock intensively after sulfur, which by the content of Markasite causes itself. Markasite is responsible for the black colouring too. That relatively yields material accepts only in the yellow zones a high gloss polish. In the black zones a silky polish remains. This material was sold as “Mustard Jasper”. As discovery site Sarawak on Borneo is given.