Extraction of Haltern silica sand, which was formed during the Cretaceous Period, is carried out entirely under the groundwater table using a suction excavator equipped with a cutting head. 
The sands mined here are much in demand, particularly in the foundry industry. At the plant, the silica sand is classified using wet-mechanical methods and separated into three types, H 31, H 32 and H 33, all of which are available as wet or dry sand. The adjacent milling facility produces MILLISIL quartz flours W 3, W 4, W 6, W 8 and W 11, as well as SIKRON flours SH 200, SH 300 and SH 500.

The silica sands from the Flaesheim deposits were formed at the same time as those of the Haltern sands, which were created in the Cretaceous (Santon) Period. These sands comprise the following types: K 31, K 32, K 23 and K 35, as well as sand for building materials, playgrounds and sports fields, and grouts and plasters.