The technique of lost wax casting in Africa has been used to produce most of the pieces commonly called “bronzes”. It is found in almost all coastal kingdoms, from Liberia to Congo, but also in most of the kingdoms of the interior, in the Sahel countries: the Akan kingdoms of Ghana and their diaspora Baoulé in Ivory Coast, the ancient Danhomè, the Yoruba kingdom of Ifè, that of Benin-City in the Niger Delta, the former kingdoms of the Inner Niger Delta, the Dogon, the Mossi kingdom of Ouagadougou and further east, the Sao of Chad, the kingdoms of the Cameroonian Grassland [1]. It is therefore widely used.

Origins of the technique

The information available today does not allow to know neither the time, nor the origin, nor the conditions of the discovery of the different techniques of copper work.

Different hypotheses have been put forward for West Africa. For some diffusionists, Egypt and Nubia would have been the first intermediaries to transfer the basic techniques of copper work, roasting and hammering in particular, from Lower Egypt or Nubia to the Sahel countries. The Maghreb countries would then have taken over. Another hypothesis, defended by Lhote and Diop, is that Africans have discovered by themselves the simple techniques of copper and cuprous metal processing.

The state of documentation today suggests that the technique of lost wax casting was introduced from the Maghreb. Evidence of this can be found in the remains of Tegdaoust in Mauritania dating back to the 9th century, while in Mali and in the Senegal Valley, the pieces date from the 10th century AD The highly elaborate works of Igbo-Ukwu in the lower delta of the Niger River date from the 9th century: they come to disturb this hypothesis, no proof being made of the contacts of this region with Islam and the countries of the Sahel. South of the equator, knowledge is even less precise, and no discovery can go back beyond the eighteenth century.

Copper supply of arts centers

The existence of this technique poses the problem of supplying the workshops and production centers with raw materials. The state of the current research does not make it possible to specify from where the artists drew the copper necessary to their creations. There are many copper mines in Africa. Some have been exploited for a very long time; those of Niger are at least since the second millennium BC. In West Africa, there are some in the region of Agadez and Azelick. Ibn Battuta, who visited the region in 1354-1355, mentioned it when he wrote: “The copper mine is outside Takkeda. People dig the ground to find the ore they bring to the city. They melt it in their houses, it is the work of slaves of both sexes … “[2]. In Mauritania,

In Central and Southern Africa, there are more deposits in Congo, DRC, Angola, Zimbabwe, South Africa and Namibia. Their exploitation does not go back beyond the 1st millennium AD Historical testimonies attest to the use of some of these mines. For the Congo for example, Filippo Pigafetta in his “Description of the Kingdom of Congo and surrounding countries” reports the existence of blast furnaces used for copper smelting, while Olfert Dapper, in his “Description of Africa” ​​( 1686) reports the existence of the mines of Angola.

As for tin, it is found on the surface in Niger in Aïr but also in Nigeria on the Bauchi plateau.

So far it has not been possible to specify which mine came from which metal. This precision is all the more difficult as the artists reused the old objects made of copper alloy. The ore was also able to circulate on the trans-Saharan trade routes, from North to South, donated to those of cola in West Africa. In fact, it is believed that Africans on the coast exchanged the much sought-after gold in the northern countries for copper they did not have. This trade would have lasted from the 12th to the 15th century and would have followed the same routes as those that led slaves and ivory to the north. Maritime traffic a century later will allow abundant quantities of copper to be found in Africa, from the coast.

In East Africa, during the same period, copper was mined from local mines. There is evidence that people preferred copper to gold for their jewelry.

Bronzes or brasses?

Copper alloys were highly valued in black Africa. In many cases they substituted for the gold of which they were approximately colored. The complexity of the process testifies to the control of the African founders. It is understandable then that in most cultures, the operation is considered “magical”, reserved for a few specialists often made up of trades to preserve the secrecy of the trade. For his success, the assistance of a master of the occult, the sorcerer, for example, was sometimes asked.

We have pointed out above that the term “bronze” has invariably been applied to most copper-containing coins. However, it is important to distinguish between bronze and brass parts. Bronze is a copper alloy with at least 5% tin. Brass is an alloy of copper and zinc. There are as many brass pieces as there are bronze in the creations of sub-Saharan Africa. Tin bronzes contain up to 10% tin; when zinc is used, its percentage can be up to 45%. Analyzes of Ifè coins, for example, show that they contain zinc or lead in varying proportions. Copper alloys have the advantage of offering objects that are stronger than those made of pure copper. These bronzes are easier to melt and mold,

Sometimes two or three other metals are added to the copper: lead and tin, or lead, tin, and zinc. This is called tertiary or quaternary bronze. The final color of the piece varies depending on the greater or lesser amount of metal added. The clearer it is, the more additional metal there is.

The stages of transformation

 

  • The realization of the moldThe production of a “bronze” is the result of a long process. The artist first modeled a clay core roughly having the final shape of the object. In general, it covers this “clay soul” of wax or, when the latter is lacking, a substance of a similar nature, capable of being consumed by the molten metal. The cactus latex [3] played this role for the works of the kingdom of Ifè. The coating of wax is more worked than the “soul” of clay: it is he who has the real form of the object. To prevent the movement of the nucleus, iron rods protrude into it.
  • The development of the “pipes” for conduction of molten metalTo allow casting of the molten metal in the mold, various techniques were used: the Ifè workshops produced “casting channels” for the metal and “casting rods” for evacuating the air displaced by the metal. fusion. In the ancient kingdom of Danhome, there was an opening to pour the metal that was spread in the space occupied by the model of wax. The channels were again covered with several successive layers of thicker clay. The piece thus becomes a gangue around a mass of wax and especially clay. The mold is allowed to dry and then put in the fire to melt the wax.
  • Metal casting and finishingThe molten metal is then gently poured into the hot mold. Care to pour the metal depends on the finish of the piece. Air bubbles should not be trapped and channels should be full to allow the metal to fill the void. The mold is then allowed to cool and then broken. It frees a piece that still has growths to remove before polishing that gives its final appearance to the object created.

    Other techniques

    Techniques other than cast iron have been used to work copper alloys: cold hammering, ribbon cutting and burin etching, wire drawing which involves drawing the copper ingot into a wire.

    The prestige of copper alloy works

    Copper and its alloys, Africans have pulled many jewels. In most kingdoms, this metal was king, especially when gold was scarce. The kingdoms of present-day Nigeria, Ifè and Benin city in particular, are models of the use of copper alloys. We made them heads of kings, royal couple portraits at Ifè. Some of these heads still seem to talk to us. Very realistic, these characters sometimes carry scarifications that recall some faces that can still be seen today in the cities of the country. Their great “classicism” made them think that these works did not come from invention and local creativity. We invented for the Africans, in the name of diffusionism, Greek or Carthaginian bronzers whose traces we could never find … Without the discovery of the bronze plates of BeninDuring an English punitive expedition in 1897, the world would never have gone to Cubism, which is constantly being talked about. These plates treated in low relief, told the warrior exploits of the kings, the religious ceremonies. They have demonstrated the existence of a brilliant court art where the characters and scenes of life take on a unique relief. We discover a perspective simply due to the hierarchy of characters in the plan.

    The musical instruments were also made with copper alloys. In southern Benin, the court music performed by the queens at Xogbonou [4] is made using a copper alloy percussion can on which rings slide. Initially she was made of iron. It is likely that the beauty of the copper alloy metal sounds led to the change. Further north, in the Fon country, the geminated bells of the “kpanlingan”, those court heralds who repeat every day at the rising of the king, the gesture of the kings ancestors, are also made of copper alloy.

    Copper and its alloys continue to be very attractive to Africans. Some have discovered the therapeutic virtues and do not hesitate to resort to it. Craftsmanship in most West African countries continues to perpetuate centuries-old forms, where copper retains all the brilliance of its yellow, beauty and joie de vivre.

    Joseph Adandé
    University of Abomey-Calavi


    Bibliographic orientation:

    Blier, P, S, 1997: The African royal art, Flammarion, 271 p
    Bruyninx, E, 1986: The art of brass among Dan and Guéré-Wobè of Haut-Cavally region (Ivory Coast ); Gent, Belgie, Faculteit van de Letteren in Wijsbegeerte, Rijksuniversiteit, 316 p.
    Cuoq, JM, 1975: Collection of Arabic sources concerning West Africa from the seventh to the sixteenth century, Paris CNRS.
    Dapper, O: Description of Africa (1686), published in Prohibited Objects, Paris Editions Dapper, 1989.
    Fagg, W, 1970: Divine Kingship in Africa, London
    Grebenart, Decamps G, 1988: The Origins of Metallurgy in Africa Occidental, Paris, Editions Errance; Abidjan, NEA, 290 p,
    Herbert, E, Red gold of Africa
    Meyer, L, 1997: Metal Arts in Black Africa, SEPIA, 175 p.
    Paulme, D: “About Kudio Ashanti” in African Presence n ° 10-11, pp 156-162
    Article “Bronze” of the Dictionary of African Civilizations, Fernand Hazan Publishers, Paris.
    Pigafetta Filippo, Description of the Kingdom of Congo and Surrounding
    Countries Ratton, Ch, “The Fetish Gold”, in African Presence, No. 10-11, pp 136-155
    Willet, F, 1967: Ife, an African Civilization, Tallandier , 232 p


    [1] Apart from these realms, another technique, that of open cast iron, is used. It is found in Gabon, Zaire, and southern Africa.
    [2] in Cuoq JM: Collection of Arabic sources concerning West Africa from the seventh to the sixteenth century, Paris CNRS, 1975, p. 318.
    [3] Euphorbia kamerunica; the process of using this latex is complex. Willet (1967: 205) gives a description.
    [4] Xogbonou is one of the names of the ancient kingdom of Porto-Novo, Benin.