Colour light grey to almost black, occasionally brownish or greenish. Dark colours of organic admixtures. Flint consists of the quartz variety chalcedony. Very dense structure, often with remnants of siliceous sponges embedded in the centre. Characteristic conchoidal fracture. A white rind forms as a result of water loss.

Formation:

Displacement of carbonates by circulating siliceous solutions in concretion-like accumulations. Occurs only in individual nodules, never in coherent layers. Usually embedded in chalky limestone, also found secondarily in glacial and fluvial sediments.

Locations:

Northern Germany, Rügen, Denmark (Mön Island), England (Dover)

Products:

In the Stone Age, raw material for weapons and equipment, in the 17th century for striking sparks in flintlock rifles (shotguns). Today occasionally used in ball mills and as a grinding and polishing agent.