Banded flint : 3D documentation

This type of flint is found in the Upper Jurrasic settlements of Świętokrzyskie Mountains. The most important exploration points and outcrops of this raw material are found on the northeastern Permo-Mesozoic ridge, in the strip running from Iłża to Zawichost (Król and Migaszewski 2009: 19; por. Krajcarz et al., 2014). Banded flint was described for the first time by Stefan Krukowski (1939). It occurs in Jurassic limestone at various depths or in its weatherings. This regards above all the concretions or paralel layers. The size of concretions varies, the largest specimens reaching even a diameter of 2 m. But the average size oscillates between few and several centimeters. Large specimens have polycentric structure whereas smaller ones have simple structure, with core placed centrally. Banded flint is characterized by irregular splitting ability, resulting from varying hardness of singular bands in flint mass. Scar surfaces vary from smooth to lightly rough or uneven. Transparency is very low and only by the edges. Characteristic trait of this raw material is the presence of lightgrey, grey and dark grey bands arranged mostly concentrically, irregularly and alternantly (reminding onion-skin; Balcer 1975: 54; Migaszewski et al., 2006; Król and Migaszewski 2009: 21; Bąbel 2015)