A gravel-pit near to the village Arcen in the province of Limburg is producing agate- and jasper-bearing gravel that was transported by the river Maas from eastern directions. The primarly source of this material is situated in the mountains of the Ardennes and the high Venn Ridge.

Very interesting informations about agate collecting are given from the following dutch agate collectors at their homepages: Günther Erkenz, Rob de Jager, Henk Rayer and Rini Saat