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Liel chert

Material name: Liel chert
Synonyms: Type 313
Material (geologic): Upper Jurassic (Oxfordian) chert

Jurassic chert from the Schneckenberg
Foto: Matthias Rummer, 2004

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General characteristics

(In part adapted from Affolter 2002
 

Geographical setting: The only known source of this type of chert is located on the northern side of the Schneckenberg, directly to the southwest of the village of Liel, just across the Rhine from Mulhouse. The area is the westernmost part of the Black Forest, which is known locally as the "Markgräfler Land". The Schneckenberg consist of Jurassic sediments with at the basis Lower Oxfordian marls covered by Middle Oxfordian limestones built by coral reefs. Formerly, this sequence was probably capped by a layer of oncolithic limestones, which is the only member of the sequence known to contain flint. This upper part of the stratigraphy has been dissolved during the Tertiary, leaving a loamy rest, very rich in iron, the so-called Bohnerzlehm, or "Bean-ore loam" after the small nodules (beans) of iron-ore it contains. In these sediments the eluvial flints are embedded, sometimes much affected by impregnation with iron, like the "Blutjaspis", but mostly to a lesser extend like can be seen in the pictures below.
Material and colour: The material in an unaltered state is quite similar to the banded, light-grey chert from the prehistoric flint mine of Kleinkems. The major difference is the higher content of micro/meso-fossils, most of which seem to be foraminifera, but some ostracods are present too. A few of the larger fossils are sometimes lined with crystalline quartz, forming micro-vugs. Colour is variable, but seems to have been originally a light grey with some brownish hues, like the Kleinkems chert. Due to impregnation with iron-salts, some nodules are a lot more brownish, frequently with red patches towards the core. In other specimens there are large areas with a strong yellowish brown colour. The similarity with Kleinkems is also clear from the cortex, which is in most cases hard and porcelain-like, with a more or less pronounced darker band underneath. Although most of the flints consist of a very fine matrix, there are some varieties that contain large quantities of coarse inclusions.
The material from Liel has been described in some detail by Affolter (2002) as "Type 313".
Other information: The Liel chert has been found in archaeological contexts in Switzerland and west of Lake Constance(Affolter 2002), but this publication is the only one in which this raw material is mentioned. On the other hand, very little research has been done on siliceous raw material use in Southwestern Germany and the adjacent regions of France, so the distribution might be a lot wider towards the west and north. As the chert from Liel is quite typical, it should be possible to differentiate it from the Kleinkems chert, and similar materials from the southernmost part of the Alsace.
Knapping notes: The knapping-properties are similar to those of Kleinkems chert, but due to the frequent inclusions and occasional cavities, it is not as perfect. As the material has been weathered out of the original enclosing limestone, and is lying in a residual loam, fissures and fractures are quite frequent, which also influence knapability negative. In all it is a good raw material, but if you should choose between Liel chert and the material from Kleinkems, be sure to choose the latter.
Archaeological description: Like already said above, not much is known about the prehistoric use and distribution of Liel chert. As Affolter has been the first to describe this type of material only quite recently (Affolter 2002), we will probably have to wait some time for the first publication in which this material is being recognized. Basing on the reasonable but not exceptional quality of the material, we expect it to have mostly local to regional significance, with only occasional pieces entering the exchange networks outside a 50 km radius around the source. On the other hand, Affolter claims to have identified the material as far as Sion in Southern Switzerland, over 170 km from the source, and on the shores of Lake Neuchâtel and Lake Geneva/Lac Léman, as well as in the Upper Paleolithic sites of Petersfels and Kesslerloch west of Lake Constance/Bodensee. This is remarkable, as the much better quality Kleinkems chert is hardly found in archaeological contexts towards the south. It has to be seen, if all this material is rightly attributed to the Liel-Schneckenberg source, or if there are other, still unknown sources that yield similar material.

According to Affolter the location we sampled at the Schneckenberg is a prehistoric extraction site, but as the chert lies in Bohnerzlehm, most extraction visible at the surface will probably have targeted the iron-ore this sediment contains, rather than the flint. As the site lies in beech woods presently, the visibility on the surface is year-round extremely limited, and knapping waste is hard to spot. Very localized cleaning of the soil underneath the litter in the early spring of 2006 showed débitage, to be present, but without further investigations it is impossible to say if the material is reworked by iron-ore mining or indeed primarily connected with the diggings. So, like so often, the only way to get some certainty is to excavate. Any volunteers out there?



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Schneckenberg
Locality: Schneckenberg near Liel, Lörrach district, Baden-Württemberg, Germany
Synonyms: Source M 1; Schliengen-Liel/Schneckenberg, according to Affolter 2002.
Geographical description: The sampling site is located in wooded country on the northern side of the Schneckenberg, a hill that rises some 100 metres over the valley in which Liel lies. As can be seen on the detailed geological map of the region (no. 8211 Kandern), the source is located directly on/near some very small patches of Bean-ore loam (unit BO). This probably accounts for the numerous smaller and larger pits which cover the ground, as can be seen in the picture below.
Geographical co-ordinates: Lat. 47° 44' 09" N
Long. 007° 35' 47" 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 were taken with a handheld GPS-receiver in wooded country, directly at the "mining"-area. Precision is within 15 metres, but as the site is probably several hectares in size, precision is not too important.
Other topographical information: Although it isn't a "park-and-knap" source (mind you, there is a possibility this is a prehistoric extraction site, so NO knapping on the spot!), it is quite easy to reach. Follow the instructions given for the source of "blutjaspis" in Schliengen to get to the B 3 and Schliengen, but drive another kilometer or so after you pass the sampling site of Blood Jasper, until you come to the village of Liel. In the village, take the fist narrow road to the right (south), which leads to Hertingen and park your car at any convenient spot. Where the road to Hertingen goes right at a T-crossing, there is a path that leads uphill towards the woods. After 300 m there is a fork in the road, where you keep right, another 150 meters, and you are directly downhill of the source, which lies on the 310 m isohypse.
Additional information: Mining site in the woods
Foto: Rengert Elburg, 2003
  As you can see in the picture above, there are quite a number of conspicuous heaps and pits in the area. These probably result from iron-ore mining rather than from flint mining. The identification of the site as a mining site, probably results from comparison with sites like Lampenberg-Stälzer, where in mountainous terrain the mining pits are still clearly visible, combined with the residual flint present in the ore-deposits. We didn't see any large amounts of knapping-waste as we visited, so we are not really convinced (yet) that it really is a full-scale mining site, but some knapping waste is present.
Visitors information: As we visit this region, we mostly stay in Freiburg, either on the Hirschberg camping or with our favorite wine maker. Some information on Freiburg can be found on the page on Kleinkems.
On two occasions, we stayed directly in the Markgräflerland, once in Steinenstadt on the camping directly in the village, another time on a lot larger affair a bit to the south of Bamlach. Although the infrastructure like showers is better on the latter, we prefer to stay in Steinenstadt, mostly because the better possibilities for eating and drinking around there.
Sampling information: We visited the site during a short trip to the region in the autumn of 2003, as we wanted to see the excavation in the Neolithic flint mine at Kleinkems (Engel & Siegmund 2005). We then used the opportunity to check out some sources in the wider region mentioned in Affolter 2002. As it was September, the ground-cover was not very dense, at least no thick carpet of fallen leaves, but visibility was not optimal. There is some material to be found on the surface, which will do nicely for a sample for your reference-collection. Until proven otherwise, we still have to keep the possibility open that it is a prehistoric extraction-site, so no digging en no knapping.
In the winter/early spring of 2006 we revisited the site, hoping for better visibility, but the ground was still densely covered by old leaves from the beech forest. We cleaned a few square decimeters in the northernmost part of the area, directly alongside one of the pits, and did indeed find quite a few small flakes. It is to be hoped, that someone will carry out some more research in the area, especially as the well-known Neolithic mining site of Kleinkems, where the chert was extracted from extremely hard limestone, is only 8 kilometres away. It would be an interesting study to see how the difference in substrate affected the mining methods as well as the distribution of the material.
  Typical chert
Foto: Matthias Rummer, 2004
 
Flake of typical chert with reddish core
length: 54 mm
Yellowish impregnation
Foto: Matthias Rummer, 2004
 
Flake with strong yellowish impregnation
length: 52 mm
  Banded chert
Foto: Matthias Rummer, 2004
 
Piece of banded brownish chert
length: 50 mm
Small flint nodule
Foto: Matthias Rummer, 2004
 
Small, prehistorically tested nodule
size: 54 mm
Sample description: N/A
  Flattish nodule
Foto: Matthias Rummer, 2004
 
Freshly splitted flattish nodule with yellow core
length: 105 mm
Coarse variety
Foto: Matthias Rummer, 2004
 
Piece of coarse flint with numerous inclusions
size: 79 mm
  Macrophoto of fossils
Foto: Matthias Rummer, 2004
 
Close-up of a small flake with clear fossils
length: 28 mm
light banded chert
Foto: Matthias Rummer, 2004
 
Flake of banded chert with some foraminifera
size: 63 mm

 

Last modified on:
February 28, 2006
Contents primarily by:
Rengert Elburg
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