Beside the finds from Malawi and Namibia, since the year 2005 also Chalcedone from Indonesia are processed in Idar-Oberstein. More exact data concerning the discovery site of this usually only weakly blue colored material are missing. Best quality of this place of discovery can show also violet tones apart from blue colours.
Jeffrey Anderson is describing on his website dwarve´s earth-treasures a purchase of agate-nodules from the same Region.
The website sumatran blue agate is given more information about this gemstone-material.