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Helgoland flint

Material name: Helgoland flint
Synonyms: Nordic red flint, Heligoland flint
Material (geologic): Upper Cretaceous (Turonian) flint

Detail of typical red Helgoland flint
Foto: Matthias Rummer, 2002

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General characteristics

(In part adapted from Ahrens 1966, Schmid & Spaeth 1981 and Beuker 1988
 

Geographical setting: View of the Düne from Hegoland
Foto: Rengert Elburg, 2002
  The very small archipelago of Helgoland lies in the North Sea, about 50 kilometres off the coast of Germany in the "Helgoländer Bucht". It consist of the two small islands of Helgoland and Düne. The difference in topography, and with it the geology, between the two is quite striking. Helgoland consist mostly of towering red cliffs while Düne is not more than a sandbank with a few dunes, protected from the pounding surf by some piers and basalt blocks, as you can see in the picture above.
Both thank their existence to a large amount of Zechstein salt deep under the sea floor which pushed up the overlying Mesozoic layers, consisting of Buntsandstein, Muschelkalk and Cretaceous sediments (identical geological sketches in Ahrens 1966 and Beuker 1988). Before the sea level rise at the end of the last ice-age, the now-islands constituted the end of a range of lowish hills which stretched west from the Holstein coast. With the melting of the ice sheets, this range became a narrow peninsula until it was cut off the mainland as the water rose to about 15 metres under the present level (Ahrens 1966). When this level was reached in the region is unclear, estimates vary between transition of the Boreal/Atlanticum around 6000 BC to approx. 2000 BC. Helgoland and Düne were at this moment still parts of one, considerably larger island, and there might have been a string of smaller islands right down to the Eiderstedt peninsula on the coast of Schleswig-Holstein. The Western part of this large island, now Helgoland, consisting of the resistant Buntsandstein, while the Eastern portion, of which Düne forms the last rest, was built of Cretaceous chalks. Both future islands were connected by a stretch of soft Muschelkalk. This connection, known as "Witte Klippe" (White Cliff), existed well into historical times, the last vestiges of it collapsed during a storm in 1711, opening the approx. 1 kilometre wide Skittgatt channel between the two islands.
The cretaceous flint bearing layers lie now under water off the Northern beach of Düne were the resistant flints, loosened from the parent rock by underwater erosion, are washed ashore.
Material and colour: When talking about "Helgoland flint" (or Heligoland as the island is called in some of the papers written in English, we stick to the spelling of the Times Atlas of the World), always the reddish variety, found not on Helgoland but on nearby Düne, is meant. Its colour has been variously described as flesh-red, pale red, purple red or even "weak burgundy" with a more or less pronounced black band under the cortex. By the Munsell scale, the reddish material we found should be called dusky red (10R 3/3-3/4 and 2.5YR 3/4-4/3) and weak red (7.5R-10R 4/3-4/4), with the darker band very dark gray to black (N 2.5-3).

What causes the colouring and banding is the subject to some debate. The reddish colour can probably be ascribed to the presence of iron oxide in the form of Fe2O3, while nearly the same amount of iron (around 800 ppm) is present in the darker band, it occurs in the form of iron carbonate. The main chemical difference between the two types is the presence of fairly large amounts of carbon (also 800 ppm) in the darker material (Krüger 1980). How this difference is to be explained is unclear. Beuker (1988) suspects it is the effect of "underwater patination", Krüger thinks the difference to be part of the formation of the flint. We are not sure which side is right. The arguments of Beuker seem convincing, as the archaeological samples, which were presumably gathered from the former cliffs, do not show this banding. Another argument could be the comparison with very similar flint from the Upper Cretaceous Scaglia Rossa in Northern Italy (link to be added), which doesn't show this kind of banding either.
The structure is fine grained, and only the thinnest splitters are translucent

  Typical rolled nodule of red/black flint
Foto: Matthias Rummer, 2002
 
Typical rolled nodule of red/black flint
size: 84 mm
Split nodule of red Helgoland flint
Foto: Matthias Rummer, 2002
 
Split nodule of red Helgoland flint
diameter: 53 mm
  Apart from the rare and typical red material, there are several other varieties of Cretaceous flint to be found on Düne. The second most typical is a yellowish type, with a colour between yellowish brown (10YR-2.5Y 5/6) and light olive brown (2.5Y 5/4). Both the red and yellow type can occur within one nodule, as can be seen on the photos at the bottom of the page. The same variation within one nodule with very similar colours can be found in the already mentioned Scaglia Rossa flint, especially the Val di Non and Monte Avena varieties, which it closely resembles.

The rest of the flint from the area can only be described as "generic Baltic/Nordic flint". It is mostly grey to gray-brown and brownish material. The spectrum of colours varies from (very) dark grey (N3-4 and 2.5Y 3/1-4/1), dark grey (10YR and 2.5Y 4/1) and gray (10YR 5/1) via grayish brown (10YR 5/2), brown (10YR 5/3) and pale brown (10YR 6/3) to strong brown (7.5YR 5/5-5/6) and reddish yellow (7.5YR 6/6).
Most of this material is quite glassy and strongly translucent. The majority pieces show distinct small white spots (see photos) or slight clouding, but quite a lot of the stuff is homogenous and featureless.

Other information: As all primary occurrences of the cretaceous layers lie now under the sea, nothing can be said about the prehistoric exploitation of the flints on or near Düne. As the sea has been eroding the soft chalks for quite some time, it is highly probable that, after greater Helgoland became an island, some kind of cliffs with flint layers were exposed during the Neolithic and Bronze Age. Quite likely the flints were either gathered from the foot of these cliffs or taken directly from the exposed strata.
Knapping notes: As the material is so rare, we didn't have any real chance to do a lot of experimental knapping. The first nodule we found, under the very mistaken impression the red material is very common, we treated with our geologists' hammer. The second nodule we just split and detached some flakes from one of the halves to get good material for the photos on these pages. It works quite nicely, a bit less splittery than the standard glassy Northern flint. As can be seen form the archaeological finds (see below), it is a very good material for axes and bifacially worked pieces, probably mainly manufactured with direct soft percussion.
The third nodule in our collection is still as intact as it can be seen in the picture above, so there is a small chance we will do some more work with it. If we do, we'll let you know.
Archaeological description: The recognition of the archaeological importance of the red Helgoland flint is one of the success-stories in the history of flint sourcing. During the fourth Flint Symposium in Bristol, a dutch archaeologist, Jaap Beuker, was listening to a talk on Northwest European flint stratigraphy by Schmid (1986). As he saw the typical red Helgoland flint, he realized that some objects from a hoard in the Netherlands were made out of this material. After this discovery, he made an inventory of all objects made from this flint present in Dutch museums, publishing his findings only a few years later (Beuker 1988, 1990).
It is a great pity that the colleagues in Northern Germany and Denmark didn't follow this example, so we only have more precise data on the use and importation in prehistory at the end of the distribution chain. In all, two dozen find spot are known in the Netherlands, the large majority of which lie in the Northeastern province of Drenthe. Most finds are polished axes or bifacially worked sickles or fragments of these, and date to the later Neolithic (Funnel Beaker/Trichterbecher culture) or the earlier Bronze Age.
In absence of further research in Germany and Denmark, very little can be said about the route along which this material was transported. For the Neolithic, there is the possibility they were transported over the still existing land bridge (see above), or by boat, island hopping along the string of islands towards the coast. During the Bronze Age, transport must have taken place by boat, but it is unclear in which direction these contacts took place or in which form the flint was distributed. It is to be hoped that in the future somebody will look further into the distribution of this easily recognized flint, the only Northern variety that can be traced to such a restricted and remote source.


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Düne near Helgoland
Locality: Düne near Helgoland, Schleswig-Holstein, Germany
Synonyms: FlintSource sample 342.
Geographical description: The only known source of the reddish Helgoland flint is the Northern Beach of the small island Düne just off the main island of Helgoland. As the island is quite small, under a square kilometre, you really don't need directions to get to the place. As soon as you have landed, either by plane or with the small ferry from the main island, just keep North until you find yourself at the beach. Here you can try your luck to find some of the very rare red nodules.
Geographical co-ordinates: Lat. 54° 11' 18.6" N
Long. 007° 54' 51.0" E
(Mapdatum WGS 84)
Co-ordinate precision: The co-ordinates given point to the middle of the Northern beach. In this area we found three of six pieces in all of the reddish flint, but don't be too precise about it. Finding your own sample will take quite a lot of walking along the beach.
Other topographical information: A trip to Helgoland is not something which is undertaken spontaneously on a rainy Sunday afternoon. As it is one of the remotest sampling sites we visited yet, we can tell you that quite some planning is necessary. As you will be wanting to visit the place off-season (see for details under "sampling information"), you first have to find out if a ferry from the mainland is running. During most of the year, a ferry leaves Cuxhaven at 10:30 AM, arriving two hours later in the roadstead off Helgoland, but better check on the homepage of the tourist board, and follow the appropriate link.
This is where the real fun starts, depending a bit on the weather. If you take the normal ship, you will now be leaving it, to be transferred with dinghies to the shore. With a bit of a breeze, this part of the journey can get somewhat adventurous, but not as much entertainment as the way back (see "visitors information"). After you have endured this part of the trip, you have to take the small ferry to Düne, running every half hour, weather permitting, from the same pier where you landed. At least, this boat has some more permanent covering, sheltering you and your gear from the spray, rain and occasional large waves. Less than ten minutes after leaving Helgoland, you will find yourself at the Eastern side of Düne. Just follow your instinct North, or the signs pointing to the "Nordstrand".
If you do not like travel by sea or have less time and more money to spend, you better charter an air-taxi and fly directly to the small air strip on Düne. Information can be found following the links on the Helgoland homepage cited above.
Additional information: Northern beach of Düne
Foto: Rengert Elburg, 2002
  In the picture above you are looking along the deserted Northern beach at Düne towards the East. You can see the steeply rising cliffs of Buntsandstein which build up most part of Helgoland in the background. The gathering dark clouds announce a slight storm, force 8 to 9, one fine September afternoon. Ideal weather for sampling, but less so for the trip and any plans to spend the night in a tent.
Visitors information: There are several possibilities to make the trip to Helgoland a nice outing, either in a more comfortable style or roughing it up a bit in the spirit of the true flint sourcerer. If you decide to do it the easy way, you best take the speed-boat to Helgoland and stay in one of the numerous hotels or guesthouses that are to be found on this very touristic island and eat in one of the restaurants on the main island. You can then take the small ferry to Düne and do you sampling during a appetite inducing afternoon stroll along the beach.
The second possibility, a bit more in style, is to rent one of the small bungalows on the camping on Düne. Information on this type of accommodation can be found following the links on the Helgoland homepage, or directly at the office near the air-strip.
The cheapest possibility is of course to sleep rough at the beach, if you don't want to carry your tent to stay at the camping just behind the dunes on the northern part of the island. As we visited at the end of September it was mostly raining quite heavily and during the night a light northeastern gale was pounding the beach, so we were glad to have brought our sturdy tent, and had packed, and this is a minor detail not to be forgotten, extra long (35 cm) V-profile tent pegs and extra guy ropes.

The only place to get a drink and something to eat on Düne is the smallish pub/restaurant on the Southern beach of the island. We had a very passable cod with mustard sauce, swimming happily in our stomachs in larger quantities of our favourite Jever pilsner, which they have on draught here.

A few words of warning about Helgoland are in place on these pages. Although belonging to Germany, and with it to the European Union, Helgoland is a tax-free area. So if you want to buy a camera, limited quantities of cheap booze and perfume, Helgoland is the place to go. This is something quite a lot of people know and do, off-season mostly senior citizens, on a day-trip. So be prepared to share the boat with a large amount of groups in the typical outing mood, with according sound level, especially during the weekend.
As booze is so cheap on the island, most people do consume quite a lot of it during their stay, which can give rise to quite hilarious moments when they are trying to board the ship from the small dinghies that ferry them out. As we were leaving, there was quite a strong breeze and the surf was still swept up by the storm of the previous night, making the short trip quite rough and wet indeed. The most amusing part was entering the ferry, with a considerable part of the passengers quite tipsy, banging the plastic bags with tax-free liquor against the board, the boat and each other, eventually pouring a very interesting cocktail into the dinghy and sea. If you plan to bunker some booze, be aware that there are customs controlling at the pier on leaving the island, and better pack your bottles somewhere secure to avoid breakage.

Sampling information: Sampling the beach of Düne can be a bit tricky during the summer (see also addition below), as it is a very popular nudist beach. Turning up fully geared, and trying to find flint nodules among naked bathers, could give the very wrong impression you are a pervert of some sort. On the other hand, it is quite hard to imagine yourself naked with hammer, camera and sampling bags, picking up flint and testing the nodules to see if they are of the desired red variety. Apart from that, you would run the risk of serious problems with other visitors, who would rightly protest at you leaving razor sharp flakes to be treaded on with bare feet. So better visit during the colder times of the year, as the beach is nearly deserted then, and the only naked bathers are the seals that lie basking here, as can be seen in the picture below. If you go off-season, be sure to check if and when the ferry is running, as you could end up stuck for a few days on Helgoland or be unable to reach Düne if the weather is too rough for the crossing.

Spring 2007: At the beginning of 2007 we got some very useful information from Norbert Rieder, a zoologist from Karlsruhe with ample experience on the biological station of Helgoland. He pointed out that the beach on the northern side of Düne is covered with a fresh layer of flint-free sand every spring, making it quite impossible to find any flint there in the summer. In this time of year, you have to take refuge to the eastern side of the islet, where large amounts of flint, dumped there suring WW II to protect the coast, can be found. But nearly all red flint over there has been collected in the intervening half century.
According to our informant there are other methods to secure the desired red flint during the season. Firstly there is a jewelry vendor at the so-called "Hummerbuden" ("lobster shacks"), small vending sheds at the quay of Helgoland itself, who sells flint at quite steep prices. But compared with the cost of a trip to Helgoland, it might be better to buy here than to leave empty-handed.
Secondly, especially if you visit during the school holidays, you will find children on the stairs towards the high ground of the "Oberland", offering red flint for very reasonable prices. The third possibility is a dealer in stones and fossils that can found at the jetty of Düne during most of the summer.

  Seals on the beach near Helgoland
Foto: Rengert Elburg, 2002
  Finding something else than normal greyish Nordic Cretaceous flint on Düne presents a problem in itself. As we visited, we tested at least 500 intact nodules to see what they looked like at the inside, picked up another thousand or so to conclude they were not interesting, and seeing thousands of pieces lying around that were clearly not what we were looking for. In all we collected three rolled nodules, two smallish broken pieces, and one flake of the red flint and only one larger piece of the stronger yellowish variety. This sets the incidence of red flint at less than 1‰ of the total. And then we were still lucky: the third nodule we picked up on the island, as we were still pitching our tent before we went sampling, was of the reddish variety, giving a completely wrong impression about the abundance of the material.
All nodules we found showed already from the outside they were of the sought after material (see picture at the introduction), with patches of red showing through the rolled cortex. We do not know if this lack of red flint is due to depletion of the source by collectors, or if the material has always been this scarce. The literature tells us the red variety is "relatively rare" (Schmid & Spaeth 1981) or plain rare (Beuker 1990), but none of the publications gives a percentage.
From what we have seen, you could very well visit the site, and leave empty handed, especially if you only come on a daytrip (but see above for some suggestions where to buy some material). Another point that should be regarded, is the fact that a lot more flint can be found during the low tide, so if you undertake the voyage, better stay over at least one night, to make sure you can walk the beach when it is at its widest. The largest amount of flint is to be found at the Western end of the beach, but we only found our yellow piece here among the thousands of nodules, none of which was of the most desired red colour.
  Piece of typical red flint
Foto: Matthias Rummer, 2002
 
Piece of typical red flint with black band under the cortex
length: 47 mm
Presumably prehistoric flake
Foto: Matthias Rummer, 2002
 
Presumably prehistoric, patinated and slightly worn flake from the beach on Düne
length: 43 mm
  Piece of yellow variety
Foto: Matthias Rummer, 2002
 
Flake of the very rare dense yellow variety
size: 64 mm
Piece of two-toned red flint
Foto: Matthias Rummer, 2002
 
Piece of flint from Düne with red and yellow variety within one nodule
length: 52 mm
Sample description: The piece left in the top row is a typical example of a freshly struck flake with the dark band clearly visible under the cortex. This darkening is probably a secondary phenomenon and hasn't been found on prehistoric artifacts. The piece next to it is a rolled, slightly patinated decortification flake we found lying on the beach. It is unclear if this is a prehistoric piece, or just the waste of another flint maniac that visited the island.
In the second row are a flake of the yellowish variety with next to it a piece of the first nodule we found with yellow and typical red flint occurring within the same nodule.

The two pieces below just serve to illustrate that most flint that is found on Helgoland/Düne is of the generic Northern Cretaceous type that can be found anywhere in Northwest Europe, either primary or as erratic, glacier transported material.

  Flake of brownish, glassy flint
Foto: Matthias Rummer, 2002
 
Flake of brownish, glassy flint
length: 55 mm
Flake of spotte grey flint
Foto: Matthias Rummer, 2002
 
Flake of spotted grey flint of the generic "nordic/baltic" type
size: 49 mm

 

Last modified on:
May 2, 2007
Contents primarily by:
Rengert Elburg
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