Foto: Matthias Rummer, 2001
- Lengfeld
Sampled sites:
| Material name: | Lengfeld-type chert |
| Synonyms: | Chert of the Abensberg-Lengfeld-type, Hornstein |
| Material (geologic): | Eluvial Upper Jurassic (Kimmeridgian/Malm ζ) chert |
|
Foto: Matthias Rummer, 2001 |
Sampled sites:
|
(In part adapted from Reisch 1974 and Rind 1993)
| Geographical setting: |
The prehistoric mining site of Lengfeld lies on the right bank of the Danube, ca. 12 kilometres to the Southwest of Regensburg in the southern part of the Franconian Alb in Bavaria, Germany. Geologically it is situated on the transition of the Kelheimer- and Bad Abbacher Wanne, two of the numerous small-scale Upper Jurassic basins in the area. The occurrence of the chert is confined to a small strip of Upper Kimmeridgian/Lower Tithonian (Malm ζ 1 in the local stratigraphy) limestones on the eastern side of the narrow valley of the Teugner Mühlbach. During the Palaeogene most of the limestones in the region were weathered and eroded, leaving the resistant chert embedded in a residual loam, mostly covered with Quaternary sediments. |
| Material and colour: |
Alas, there is no such thing as typical chert of the "Lengfeld-type", whatever there is written in the archaeological literature. The material mostly occurs in the form of flattish nodules (Fladenhornstein), but some round nodules (Knollenhornstein) and occasionally even tabular material (Plattenhornstein) can be found here too. The lumping together of the cherts from Abensberg-Arnhofen with the material from Lengfeld (Grillo 1997) however looses valuable information, as the typical banded tabular chert of Abensberg is really confined to the basin of the Abensberg-Pullacher Wanne. When creating a material type covering the very similar gray, banded cherts of the larger region, it should be called "Jurassic chert from the Southern Franconian Alb" as similar materials can be found on several sites like Alling/Thalhof, Herrnsaal/Kelheimwinzer and even in the Eichstätt-region.
The colour of the chert in Lengfeld is highly variable from light gray (N7), very pale brown (10YR 8/2 - 7/4) to gray (N5 and 10YR 5/1), dark gray (N4), very dark gray (N3) and black, but quite a lot of the material, especially the darker colours, has a slight bluish hue like dark bluish gray (10B 4/1 to 5PB 4/1). To make things even more complicated, part of the material has been infiltrated with iron salts to give it a yellowish (10YR to 2.5Y 7/7), yellowish brown (10YR 5/6) or even strong brown (7.5YR 5/6) colour. |
| Other information: |
Lengfeld is one of the very few sites in Germany where mining has been proven and where excavations have taken place. The first dig was undertaken in the 1930ies, as the site was interpreted as a settlement of a "macrolithic Mesolithic" culture, with similarities to the Western European Campignien. At the end of the 1960ies, new excavations took place, under the direction of L. Reisch, who rightly reinterpreted the site as a (Neolithic) mining district, making it a major site in the history of mining archaeology. Recently the local archaeological service under M. Rind has carried out rescue excavations in the same area, confirming the presence of mining pits and even shafts dug into the residual loam. |
| Knapping notes: | Even one of the original excavators has been forced to acknowledge, that the silex from Lengfeld is only of mediocre quality (Reisch 1974), and can't be compared to the really high quality long-distance materials. As we did only take a small sample of surface material, we didn't do a lot of experimental knapping on this material. Some of the larger pieces we tested showed it to be of reasonable quality, but certainly nothing special, but it shouldn't be forgotten that most nodules still present represent the discarded material of the mining site and as such are a negative selection. |
| Archaeological description: |
There seem to have been at several periods of prehistoric activity on the site, covering an area of at least one hectare. The oldest lithics date to the (Upper) Paleolithic but have been reworked during the later mining, so nothing is known for sure about active extraction during this period. The mining itself has been carried out in three phases. It starts with the extraction of the flint from the residual loam in open pits. After that, the spoilheaps that resulted from the first phase were re-exploited by shallow pits. In the last period there is a full scale mining operation going on with shafts of up two metres deep and about one and a half meters wide that reach into the weathered limestone. A radiocarbon dating from the fill of one of these deep shafts gave with 5670 ± 180 uncal. bp (Hv-17009) a Middle Neolithic date for this latest phase. This could mean, that the oldest phase could date to the Upper Paleolithic, especially as there has been large-scale reworking of the topsoil between the older and the youngest phases. Nothing much is known about the distribution of the chert from Lengfeld in prehistory, but it seems that at least in the Later Neolithic lithic artefacts from the material are present on several sites in the immediate surroundings. In all, Lengfeld will have been more of local importance than the neighbouring sites of Abensberg and Baiersdorf. |
| Locality: | Lengfeld, Kelheim district, Bavaria, Germany |
| Synonyms: | "Lengfeld-Süd"; "Feldl"; Mining site D 2 according to the catalogue of the museum in Bochum, 3rd edition (Weisgerber et al. (eds.) 1999). |
| Geographical description: | The site is located on a small spur overlooking the narrow valley of the Teugner Mühlbach, directly to the south of the village of Lengfeld. Most of the higher ground where the excavations were carried out is now build over. |
| Geographical co-ordinates: |
Lat. 48° 54' 50" N Long. 012° 00' 23" E (Mapdatum WGS 84)  click here for a detailed topographical map (27 KBytes) or here for a map with further sites in the Regensburg region. |
| Co-ordinate precision: | The coordinates given here are for the spot indicated on the detailed geographical map. This is the middle of the field were most of our sample comes from. The highest concentration of chert, with a lot of cultural material, lies slightly to the Northwest, at the foot of the low spur. The mining areal lies still a bit more to the north, on the spur itself which is now completely build over. |
| Other topographical information: | The site lies just of the main road B16 which connects Ingolstadt with Regensburg, which also passes the famous site of Abensberg. Have a look at the detailed topographical map to see how to reach Lengfeld and the sampling site. |
| Additional information: | 
Foto: Rengert Elburg, 2000 |
| In the picture above you are looking from the South towards the slight spur where the shafts were excavated, now under the rather new houses. And yes, we know that this photo is not of the quality you are used to on these pages, as this is another print of a negative that was developed like a slide. Still we show it to give you at least an impression of how the site looks. | |
| Visitors information: | During our excursion in the area, we stayed in Kelheim, as this is the most central place for the different sources in the area. The nearest place to look for a bite, beer or coffee is Bad Abbach, about 4 kilometres to the Northwest. |
| Sampling information: | 
Foto: Rengert Elburg, 2000 |
| We visited the site in early spring, and though there was quite some overgrowth on the field, there were enough patches of bare soil to find sufficient material for a decent sample. Most of the chert we found comes from the area in front of the hedge in the site-photo above, where this picture was taken too. |
 Foto: Matthias Rummer, 2001 Flake of typical grey chert from Lengfeld |
 Foto: Matthias Rummer, 2001 Fragment of black "Hornstone" |
| Sample description: |
The two pieces showed above are of the type of higher quality chert that we consider to be typical for this source. The slightly banded piece on the left is a freshly struck flake 33 mm wide. The more homogenous darker piece next to it was also detached from a larger block and is of similar dimensions (35 mm wide). The piece on the left hand side below is one of the few cultural pieces we took. It is a roughly worked core on a flattish nodule with a thickness of nearly two and a half centimetres. The rusty spots are probably scratches from a plough. Next to it is an example of finer and coarser material occurring within the same nodule (width 60 mm). The small nodule, measuring 60 x 20 millimetres at the bottom row is one of the secondary coloured pieces with the "typical" dark band directly under the cortex. Again, the rusty scratches are caused by ploughing. |
 Foto: Matthias Rummer, 2001 Patinated core |
 Foto: Matthias Rummer, 2001 Example of coarse grey chert from Lengfeld |
|
 Foto: Matthias Rummer, 2001 Nodule of secondary coloured material |
| Last modified on: February 16, 2002 |
Contents primarily by: Rengert Elburg |
Comments to: |