The Virtual Corkscrew Museum's Daily Newspaper
Tuesday, June 3, 2003
Wirtz, Virginia - Following up on our ***Special Gallery of New Corkscrews Edition*** and Don Minzenmayer's May 10 comments on Laser Modelling, we are pleased to present this study by Jens Arnbjerg from Denmark. This article first appeared in the 2002 News Bulletin of "Helix Scandinavica."
On ebay and other places where antiques and other collectible item are sold suddenly a new type of corkscrew appeared the last 6 - 9 months. They are found first of all in US both also in Western Europe. They are sold under a variety of declaration from ivory to bone and unique item - all claimed to hand-carved some claimed to be "old items". The price varies from 25 to some hundred dollars, but since May 1st 2003 the trading is really slowing down.
The discussion among specialists has been hectic and several statements have been made in different directions. As many of the figures are very much a like it has been postulated that they are manufactured mechanical or even cast or compressed melded. However, nobody has been able to locate the real producer not even the country from where they are coming as well as the age of these suddenly appearing items. China, Indonesia and even Africa have been suggested. It might very well be outside Europe, as the tradition in Western Europe was not to use brass in the worm production. They all have the same shape and eroded condition of the worm. Some of the models have a carved sheath screwed on the handle to cover the worm - others do not.
I, myself, got the first piece in my hands at a street flea market in Paris, France, January 25th (this year!!). It was a very nice hand-carved dog's head figure with a decorated sheath screwed on the handle with a milled rapid shaped worm made out of brass, but it was quite eroded (artificially??). The seller claimed it originated from the Ivory Coast on the west coast of Africa.
My first impression was that it was hand-carved bone because of the typical small black spots/lines in the yellowish material. The items are made out of several different parts - put together with glue and small tenons. I could immediately see it could not be ivory -as the black lines are not seen in ivory - so I got it down to an reasonable price - The black spots are the rest of the blood vessels running longitudinally in the bigger hollow bones. The crossing arch-like stripes which most of the time can be seen in ivory are without blood vessels and very compact. Neither bone nor ivory will burn if you test it over a gas lighter - plastic-material will melt or burn.
Since then I have bought items with the same type of worm in Copenhagen, Canada, Belgium, Germany and United Kingdom - so they are available all over the Corkscrew world.
As the mature long bones are hollow in the middle (filled with yellow fat) and more spongeous in the joints-ends. Therefore their ends have to be cut off, as they are not good for carving. The open ends therefore have to be closed before carving and that is done with another piece of bone - glued or kept together with tenons.*
To convince skeptical people, I took some radiographs of the corkscrews. One can see straight black lines on these radiographs which represent either just lack of material or the gluing material, which do not absorbed the X-ray beams as much as the bone material. One can in this way appreciate the different pieces that compose the whole figure. Looking very carefully on the radiographs it is now and then possible to observe the arch lines (trabecular pattern), which very often are seen on radiographs imaging the long bones internal structure. On radiographs one can see that the worm is screwed into the material, but several haves shown some extra gluing material in connection with the neck of the worm. Even to convince the very mistrustful people, I even made histological microscopically examination of a very small piece of the material and that proved again that it is genuine bone.
It is however very hard to confirm what kind of bone - what kind of animals the bones are from - but the finest bone with the smallest amount of blood vessels comes from the mitshafts of the long bones from sheep, reindeer and cows, but also bones from deer, elk and horse can be used. In the "Syroco" figures it is probably bone-size like the metatarsal or phalangeal bones from goat or deer. In Africa even camel-bones has been used by the carvers. The different animals have a slightly different colour, the whitest being from deer and elk, but the colour can also change due to bad preparation (inefficient extraction of the internal fat) or if the items are exposed to the sun and heat.
As some of the bones have some fissure lines they can be quite old, but these lines can also be a matter of a poor quality of preparation of the bone material. The can arise if the bones are dried to rapid after boiling to get rid of the soft tissue and the fat in the bones.
Some of the figures are painted. The painting is very carefully and proper made so it cannot easily be rub off. All the human-like figures have a "SYROCO" logo under the soles on bottom, but the figures symbolizing different animals, mermaid or non-standing figures do not have any logo. On the sheath of the donkey-head there is engraved a coat of arms with some France words. It is not Latin, which often is used for words on coat of arms. The bones are all polished and treated with lack or other shining material and some are treated with a black/and or red powder, which can be removed with a brush or a towel. It is probably put into the carved groves in order to make a kind of shadow/ patina?
This is for me the most significant evidence that these corkscrew could very easily have been made a very few months or years ago. Therefore my conclusion is that the material is bone and they are all hand carved in a very nice and skilled way as there are only very small and simple differences. Those hawing a sheath fit very correct with the carved and painted connection between the sheath and the handle. They are certainly neither made of ivory nor need to be antique items (> 100 years old).
*Other material, which can be taken into consideration are: Ivory, Teeth and Antler. In cooperation to bone these materials are nearly dead material. Teeth are composed of About 95 % of inorganic material - antlers only 35% and bone 75 % inorganic material. That gives the different material it hardness but also tells about the structure. The teeth have no vessels and never had during the development - except for the medulla cavity in the centre of the teeth. From there the cavity is filled out and the cavity slowly getting smaller and smaller as the teeth grows.
Laying down minerals around the blood vessels forms the bones and the antlers and in the antlers the vessels are filled out with the minerals just before the growth is finish. The hair over the calcified antler is only in function in the growth period as it serves as the nutritional supporter with blood vessels to the growing antler. The antler will fall off and be re-growing every year. Therefore the inner structure of the antlers is spongeous. When the covering hair is dying it is warned off by rubbing the antler against trees and alike. The rest of the blood and dirt will therefore stain the outer layer of the antler grey or brown more permanently, but just under the surface there will be bonelike material, just that it will be more powder-structure and grey in colour. Very seldom the blood vessels can be found in the mature cortex, but the middle will be very sponge us. It can be used to carve different figures into.
The bones are mostly consisted of inorganic material, but it is still alive and rebuilds regularly - that is why a fractured bone can heal. The turn over of different bones are very depending of the amount of dense cortex, which is slow, and the spongeous bones like the ribs and pelvic bones, with has a more rapid turn over. The denser the compaction is -the fewer blood vessels - the better for carving.
The preparation of the bone before carving is very important for the quality of the carving. The bones has to be boiled together with some degreasing material e.g. washing soap to get rid of the fat - so it has to be very efficient e.g. 2 times 1½ hours. After all the fat is away it has to be bleached - so that the blood vessels will be lesser visible, but they can still be seen under a magnified glass and felt by the carefully observer (experienced corkscrew collector!). After the treatment the bones have to be dried before the carving process can start. This drying process has to be slow and not in the sun. If not the result will be cracking and miscolouring the bone - so cracking and/or miscolouring is not always a sign that the item was made long time ago.
©2003 Don Bull, Editor