Striped flint

Striped flint
A ball of striped flint

Striped flint (sometimes called banded flint) – a version of flint, with more or less regular system of concentric dark and pale stripes, resembling rolling waters.

Use

A large striped flint deposit is located in Lesser Poland, near the cities of Sandomierz, Ostrowiec Świętokrzyski and Iłża. Because of its rarity and unique look, local striped flint is in use today in jewellery[1] and has become a regional export product.[2]

Striped flint was mined by Neolithic people near Krzemionki Opatowskie village around 4,000 BC, and it was used in manufacturing of axes.[3]

Geology

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.[4]

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.[5]

References

  1. ↑ Bożena Ewa Wódz: Trzydzieści pięć lat krzemienia pasiastego w biżuterii (Thirty five years of striped flint in jewellery), Muzeum Okręgowe, 2008, ISBN 9788388295324
  2. ↑ Elżbieta Dziadosz, Radosław Tarkowski: Krzemień pasiasty z okolic Ostrowca Świętokrzyskiego nową wizytówką Polski (Striped flint from Ostrowiec Świętokrzyski as a new Polish flagship)
  3. ↑ Wojciech Borkowski, Janusz Bodziszewski: The use of striped flint in prehistory, Archaeologia Polona, vol 33:1995, pp. 71-87, PL ISSN 0066-5924
  4. ↑ Paweł Król, Zdzisław Migaszewski: Rodzaje, występowanie i geneza krzemieni. Zarys Problematyki. Historia krzemienia (Types, localization and genesis of flints. Outline. History of flint), Muzeum Narodowe w Kielcach, 2009, p. 25
  5. ↑ Paweł Król, Zdzisław Migaszewski: Rodzaje, występowanie i geneza krzemieni. Zarys Problematyki. Historia krzemienia (Types, localization and genesis of flints. Outline. History of flint), Muzeum Narodowe w Kielcach, 2009, p. 45
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