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Tüllingen silexite

Material name: Tüllingen silexite
Synonyms: Tüllingen chert; type 341
Material (geologic): Upper Oligocene (Chattian, Paleogene) lacustrine chert

Detail of freshwater chert
Foto: Matthias Rummer, 2007

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General characteristics

(In part adapted from Geyer et al. 2003 and Affolter 2002

Geographical setting: The Tüllinger Berg is the last hill of the Markgräfler land in the southwesternmost corner of Germany, directly at the border with Switzerland. The highish hill (max. 460 m) is flanked in the west by the Rhine valley and in the east by the Wiese river, wedged between the German border-towns of Weil am Rhein and Lörrach. Due to the complicated tectonics in this part of the Upper Rhine Graben the hill forms the core of a small basin (Flexur-Randmulde von St. Jakob-Tüllingen) filled with Oligocene sediments (Geyer et al. 2003, esp. fig. 87).
The topmost layer of these sediments are the Tüllinger Süsswasserschichten, freshwater deposits of Upper Chattian age, consisting of gypsum-marl and limnic chalks and limestones. In the upper part of the latter carbonate material nodules of siliceous material can be found. As there is no adequate name for this material, neither in the geological, nor in the archaeological literature, we herewith propose the name of Tüllingen silexite for this type of Paleogene chert.
Material and colour: The siliceous material of Tüllingen is closely related to similar lacustrine cherts of Cenozoic age like Romigny-Lhery (Eocene), Etrelles-et-la-Montbleuse (Oligocene), Mer & Suèvres (Miocene) and Jablines (Eocene), and other materials, notably from the Paris Basin, commonly, if not always correctly, known in French as "silex Bartonien". The Tüllingen silexite is a relatively unknown material, which has been described in the geo-archaeological literature only once as "Type 341" by Jehanne Affolter in her survey of lithic materials from the Jura and contiguous regions (Affolter 2002). Here it is defined as a lacustrine chert from a shore-near facies with a wackestone to packstone structure with numerous, also larger, inclusions. The colour is given as 10YR6/1-3 (gray to pale brown) and 5Y8/1 (white).
This corresponds well with the material in our sample, although some pieces are clearly darker (10YR4/2, dark greyish brown) with very dark streaks and zones, especially under the cortex (10YR3/1-2, very dark gray to very dark grayish brown). For a more detailed description of the material in our sample, see below.

We have to correct here two imprecisions in the literature where the material from Tüllingen is mentioned as "chalcedony": Zimmermann 1995 (pages 44 & 147) and Löhr 1990 (fig. 46). Even if the main constituting mineral is chalcedony, it should be called a lacustrine chert or Tertiary silex to distinguish it from volcanic-related chalcedony like the material from Slanec and similar sources.

Other information: Although the parent material of the silexite, the Tüllinger Kalk, was a very popular building stone which was quarried in numerous smaller and larger pits, nothing is known about the exploitation of the chert. As the whole area where the chalk/limestone is present at or near the surface is wooded, nothing much can be seen of possible prehistoric workings. Judging from the fact that the material has been completely unknown until recently, the Tüllinger Berg will never have been a major centre of lithic production.
Knapping notes: We can't say very much about the knapping properties of the Tüllingen chert, as our sample consist only of small pieces that were collected on the fields below the top of the hill. Some fragments, mostly of the fine-grained variety, show a good conchoidal fracture, but others are severely flawed by cavities and more crystalline patches. We hope to find a good exposure sometime, as according to Affolter (2002), some of the pieces found on archaeological sites in Switzerland show the nodules to have been of large dimensions. This could mean there have been nodules present that are comparable to those of Romigny-Lhery, with which material the chert is comparable
Archaeological description: To our best knowledge the "Tüllingen silexite" has never been recognized in any other study than that of Affolter, but raw-material oriented research in the (wider) region is very limited indeed. Even if it is mentioned in one other study of raw materials in the Markgräfler Land (Kaiser 2006: 119), no information is given there on its prehistoric use or distribution. Therefore we don't know if its scarcity in the (documented) archaeological record is due to its restricted prehistoric use, or if it's one of these cases where a siliceous raw material is actually quite common, but it goes unrecognised or is falsely identified as a better known material. The last case could very well apply because of the similarity of the material to the much more widely know cherts that are collectively known as "Silex bartonien"/Bartonian flint or "the Romigny-Lhery Type".

As "Type 341" artefacts of Tüllingen chert have been published from three sites in Northern Switzerland: Pleigne/Löwenburg (which itself is a prehistoric mining site) and Alle/Pré-Monsieur (another known source of Jurassic chert), both mousterian sites (Affolter 2002: 168), and the excavation of the Late Neolithic megalithic tomb at Aesch near Basel (Aesch-Dolmengrab, Affolter 2002: 200).

We hope that by describing this raw material in some detail here, local researchers will be more aware of the presence of this type of chert, and might be better able to recognise it in their assemblages. Any information on this silex and its prehistoric use is very much appreciated, so if you know of other publications mentioning it, or know of archaeological sites where it has been found, please let us know via the webmaster e-mail address at the bottom of the page.

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Tüllinger Berg
Locality: Tüllinger Berg, Lörrach, Baden-Württemberg, Germany
Synonyms: Käferholz; FlintSource sample 424.
Geographical description: The Käferholz is a wooded area at the top of the Tüllinger Berg, just west of Lörrach in the southwesternmost tip of Germany, directly at the border with Switzerland. According to the local geological map (Vorläufige Geologische Karte von Baden-Württemberg 8311 Lörrach, 1997), this is the only area where the Tüllinger Kalk can be found at or near the surface. These sediments (signature "TK") are only present in a very narrow strip approx. 3 kilometres long and not more than 250 metres wide, more or less following the 400 metre contour-line between the villages of Tüllingen, Ötlingen and Tumringen.
Numerous quarries have been active exploiting these limestones, but all have been filled during the previous years, so, as far as we know, no primary exposure with chert is accessible at the moment.
Geographical co-ordinates: Lat. 47° 36' 19" N
Long. 007° 38' 03" E
(Mapdatum WGS 84)

In cooperation with our technical partner I/O-graph, we offer a transformation-service for the coordinates of the sampled sites. Just click here to send a mail.

Co-ordinate precision: The coordinates (taken with a GPS receiver) point to the field just below (to the West) of the Käferholz wood where most material was collected. According to the literature (Geyer et al. 2003: 384-385), there might be some possibility to find loose material alongside the road around 47° 36' 37" N/ 007° 38' 18" E, and there is a small abandoned quarry at 47° 36' 34" N/ 007° 38' 02" E, but it isn't clear if the siliceous nodules are exposed here, and we didn't check either (yet).
Other topographical information: The site can be reached from the west via a narrow road from Haltingen (and with it the B 3 main road as well as the A motorway) towards Tüllingen and Obertüllingen, as well as from Lörrach in the east. But as there are many twists, turns and forks which can get you utterly lost in the German-Swiss border region, you better bring a good topographical map like the 1:25 000 from the Landesvermessungsamt Baden-Württemberg, sheet 8311 Lörrach, although it doesn't cover the southern point of the Tüllinger Berg with Obertüllingen, for which you will need sheet 8411 Weil am Rhein.
On the other hand, the hill is by far the highest point between Haltingen, Weil am Rhein and Lörrach, so as long as you keep going uphill, you will ultimately find yourself in the Käferholz wood.
Additional information: Sampling location on the slope of the Tüllinger Berg
Photo: Rengert Elburg, 2004
  This certainly isn't the nicest view you can get of the Tüllinger berg and the surrounding countryside, but this is the area where we did our sampling. As we collected the material on the road from Freiburg to Singen, we didn't do a detailed survey of the area, and just picked the most convenient spot to do some fieldwalking.
Visitors information: Tüllingen is ideally located for a visit if you are doing a larger tour of the region (see menu at the left of this page) and is easily reached from the main A 98 Autobahn, which links the three-countries corner with the Bodensee/Lake Constance region. For those who prefer larger cities and have a bank account that can support such preferences, Basel would be the first choice to stay. Basel lies just over the Border with Switzerland, is a very nice city with ample hotels, restaurants and some very worthwhile museums, but extremely expensive.
Those who have to operate on a more restricted budget will prefer to stay at the German side of the border, or put up their base in the southern part of the Alsace in France. More information on the infrastructure in the Markgräfler Land and especially Freiburg can be found on the pages on Kleinkems and Auggen, information on the Alsatian Jura/Sundgau will be coming up.

For those among you that are interested in non-flint-related trivia, and have noticed that sources of flint are often located at or near (ancient) battlegrounds: The Tüllingerberg/Käferholz is another example. Here a fierce battle was fought between forces of France and the (German) Holy Roman Empire during the War of the Spanish Succession in October 1702. This battle is known in German as "Schlacht am Käferholz", in English as the Battle of Friedlingen, and depending on whose side you take, either side was victorious, which means that many lives were lost for no gain at all. There is a small monument for the not-so-victorious but unbeaten Grand Duke of Badenia commemorating this historic event.

Sampling information: Like already explained under the sections above, we didn't do much looking around at the site, so there might be better places to look for chert than those marked by the coordinates given. Hopefully we will be able to locate a primary exposure in the future, especially as we are very much interested in the size and form of the original nodules. If you happen to know of a better exposed place to sample the Tüllingen silexite, we will be glad to hear from you.
  Typical chert
Foto: Matthias Rummer, 2007
Typical brownish grey lacustrine chert
size: 40 mm
Brown chert with cortex
Foto: Matthias Rummer, 2007
Brown silexite with irregular cortex
size: 38 mm
  Coarse material
Foto: Matthias Rummer, 2007
Coarse material with deep white patination
length: 33 mm
Patinated piece
Foto: Matthias Rummer, 2007
Completely patinated piece of Tüllingen chert
length: 33 mm
Sample description: Looking at the pictures you might find nine photos of this obscure material a bit of an overload, but as this is the first time the Tüllingen silexite is being described in more detail, we wanted to show the complete range of variation, as far as our sample is concerned.
The best quality material can be seen left at the first row, above as well as below this description. With the piece first piece, the main colour is 10YR6-7/1-2 (gray to light grey and light brownish grey) with the darker band under the cortex 10YR3-4/1-2 (very dark gray to dark grayish brown). The piece below is slightly darker and of a bit higher chroma with the main colour 10YR5/2 (grayish brown), the lighter areas 10YR6-7/2-(3) (more or less light brownish gray). Note the rusty schliers (above) and spot (below), 5YR4/6. Look at the high-resolution photo of the piece below to see the remnants of a fossil, most probably a gastropod, near the bulb of percussion, next to the rust stain. Both pieces will probably be of the type that has been used archaeologically, as this is good-quality material, very similar to the Tertiary cherts from the Paris Basin.
The flake to the right in the top row is a bit less fine-grained and more colourful, with the darker core around 10YR5/3-4 (brown to yellowish brown) and the lighter material around it 10YR6(-7)/3-4 (pale brown to light yellowish brown and very pale brown). Note the rough irregular cortex and a chalcedony-lined cavity. The left-hand piece in the second row is coarser still, main colour 5N to 2.5Y5/1 (gray)and lighter matrix 2.5Y6-7/2 (gray to light gray). The rusty spots are not a natural feature but plough-scratches, and the white band along the border deeply patinated material. Together with the heavily patinated piece next to it these photos prove that the material is quite susceptible to weathering, in contrast to what has been described by Affolter (2002: 259).

The small flake in the right-hand photo, first row below is an example of corser, more crystalline chert with an irregular fracture pattern. The colour is mainly 10YR7/2 (light gray) with some specks of 10YR6/3-4 (pale brown to light yellowish brown). In the second row below there is a piece of a more orange variety, 10YR6/6 (brownish yellow) with some lighter patches 10YR6-7/3-4 (pale brown to light yellowish brown and very pale brown) and the slightly darker areas 10YR5/3 (brown) and piece of slightly more translucent material of reasonable quality, main colour 10YR7/1-2 (light gray), the darker matrix 10YR5(-6)/1-2 (gray to grayish brown/light brownish gray) and the browner part 10YR6/6 (brownish yellow)

The large flake at the bottom consist mostly of the lighter, slightly crystalline variety, colour 10YR7(-8)/2-3 (light gray to very pale brown). The darker areas are denser, more fine-grained and show a better conchoidal fracture, even though there are numerous cavities present. In the slightly underexposed area in the left-bottom corner there are again numerous fossils, some of which are certainly of gastropods. The darker material varies from 5N and 10YR5-6/1 (both plain gray) to 10YR6/2, light brownish gray.
As this flake was struck from a fragment of a nodule with hardly any cortex, it shows that there must have been quite large nodules present.

  Dark chert
Foto: Matthias Rummer, 2007
Small flake of good quality chert.
Note fossil gastropod at the upper left side
size: 30 mm
Lighter coarse variety
Foto: Matthias Rummer, 2007
Very coarse variety of Oligocene chert
size: 26 mm
  Brown variety
Foto: Matthias Rummer, 2007
Light brown variety with cavity
length: 38 mm
Lighter silex
Foto: Matthias Rummer, 2007
Light-coloured, medium-grained silexite
length: 40 mm
  Large flake
Foto: Matthias Rummer, 2007
Large flake of mediocre quality
size: 68 mm


Last modified on:
December 29, 2007
Contents primarily by:
Rengert Elburg
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