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Material name: CN8c
Synonyms: N/A
Material (geologic): Late Cretaceous (Senonian, Campanian) flint

Macroscopic view of wackestone flint
Foto: Jehanne Féblot-Augustins, 2005.

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Material description

Mode of occurrence: A single fist-sized regular nodule.
Cortex: Thin, smooth and worn, transition sharp.
Colour: Brownish yellow (10YR 6.5/6).
Pattern: Featureless.
Appearance: Homogeneous material, dull and opaque, dry, quite rough, medium-grained.
Structure: Distinctly fluidal arrangement of grains.
Texture: Wackestone.
Matrix: Subtranslucent.
Grains: 25 %, pale, rounded with high to low sphericity or irregularly shaped, poorly sorted (mean size 100 µ, foraminifera of 250 µ, long spicules of 1000 µ).
Grain composition: Mainly long monaxon thin-walled sponge spicules, some globose planktonic foraminifera, bryozoan fragments (?).
Further information: Click here for the original French description (opens in a new window), or here for more information on the attributes used in the description (use your browser's "BACK"-button to return here).
Citing: Information on citing this page can be found here.

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Breignes-Pierre-Feu 2
Locality: Poncin / Breignes - Pierre-Feu 2, France, Ain department
Synonyms: Sampling site Bugey 34 after Féblot-Augustins
Geographical description: The source is located near a narrow road/path on a slight rise between the hamlets of Chenavel and Breignes, a bit over half a kilometre to the west of the latter, and somewhat more than 2 kilometres SSE of Poncin.
Geographical co-ordinates: east/x 838.2
north/y 2122.9
(Lambert zone II, NTF)

This corresponds with
Lat. 46° 03' 52" N
Long. 005° 24' 58" E

Co-ordinate precision: The Lambert-coordinates given were read from a detailed topographical map, and are within 50 metres of the precise location.
The latitude/longitude coordinates are a direct transformation of these data on WGS84 and have the same accuracy. They are given to the apparent high accuracy to prevent the introduction of a rounding-error.

The location can be found on the 1:25 000 topographical map sheet 3230 W of the French Institut Géographique National.

Geology: The embedding materials are, according to the geological map, Late Miocene (Tortonian) continental sediments, belonging to the stratigraphic unit m2bC. The reworked flint of the CN8c-type originates from Late Cretaceous (Campanian) limestones.

Map of all sampled localities of Late Cretaceous flint in the Bugey (PDF, 54 KB, opens in new window).

Type of source: Secondary. Redeposited Campanian flint from Miocene sediments.
Other types of flint: Apart from the singular CN8c-type, other Late Cretaceous flints of the types CN1a and CN2a can be found here, as well as the Middle Jurassic Bt material and Early Cretaceous Ht1 flint.
  Nodule of CN8c flint
Foto: Jehanne Féblot-Augustins, 2005
Flake with wackestone texture
Foto: Jehanne Féblot-Augustins, 2005


Last modified on:
November 15, 2005
Contents primarily by:
Jehanne Féblot-Augustins
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