Polished slab of banded/stripped flint with alternating light and dark beige/brown "bands" enclosed in host rock matrix from Krzemionki, in the Świętokrzyskie Mountains known for prehistoric flint mines.
Striped flint was mined by Neolithic people near Krzemionki Opatowskie village around 4,000 BC, and it was used in manufacturing of axes.

Upper Jurassic (Oxfordian) striped flint from Lesser Poland consists mainly of α-quartz. Morphology of grains indicates that the quartz is not a product of opal and chalcedony conversion, but it precipitated directly from the seawater. The crystallinity is higher in the centre of a concretion. Sometimes chalcedony is present, being a product of recrystalization of opal. Other minerals can be found in small quantities: clay minerals, iron oxides and hydroxides, calcite, feldspar, mica, glauconite, zircon, tourmaline and rutile.

Different colouring of individual bands is linked to an increased and decreased number and size of pores that brought about different light reflection. Fewer and smaller pores reflect less light.

Yellowish fluorescence in UV SW