Bimszand (of German Bims = pumice stone) is "fly sand", a loose porous and light material of volcanic origin.

Bimszand is volcanic glass of foamed magma that is of phonolic composition. It has emerged in prehistory as a deposition of fine parts (grain size less than about 8 mm), which were erupted from the volcanoes in the Eifel during eruptions. It is found on both sides of the Rhine at Andernach and Neuwied.

As such, the term bimskies, which has a somewhat larger grain size and seems more like gravel and can be used as an additive for light concrete.

Characteristic properties are: the high porosity and the associated low moisture density. The pumice mass varies in quality from about 800 kg / m³.

Bimszand is imported from the German Eifel region for the Benelux.

Bimszand is used, inter alia, as lightweight supplementary material in areas with less load-bearing substrates, using coarser material and, in Germany, in the production of lime sandstone. In addition, it finds application as abrasive.

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