Les mines de fer de Compong-Swai au Cambodge [Kompong Svay Iron Mining, Cambodia]

The author, a French civil engineer and hydrologist, was also an avid hunter and thus explored the remotest parts of Cambodia in the 1870s and early 1880s. The iron mines of Kompong Svay, in the Phnom Dek area, and the ore treatment by the local ​“Cuys” (Kyu people) are thoroughly described in this short report. He highlights the high quality of the iron produced there.

The Kuy (កួយ kh, กูย th) are an indigenous ethnic group, with their native lands spreading from the southern Khorat Plateau in northeast Thailand east to the banks of the Mekong River in southern Laos and south to north central Cambodia. In Cambodia, the Kuy — meaning ​“people” in their dialect, a form of Katuic language of the Mon-Khmer language family — constitute one of the twenty ethnic minorities, and are historically known as skilled iron makers and mahouts (elephant trainers). Around 40,000 Kuy live today mainly in the provinces of Preah Vihear, Steung Treng, Siem Reap, and (northern) Kompong Thom. 

Technique 

“Sur une aire d’argile, inclinée en forme de dos d’âne, ils bâtissent, avec l’argile jaune qui abonde dans le pays, une caisse rectangulaire de 2,5 metres, sur 1,2 metre, dans laquelle ils étendent des couches alternées de minerai en petits grains et de charbon de bois. La combustion est activée par deux souffleries à jeu discontinu placées sur les grands côtés de la cuve; une dizaine de tuyaux d’argile prennent l’air dans un récipienL d’argile dont la paroi supérieure mobile est formée par une peau de cerfmouillée; en soulevant cette peau et la comprimant sous son propre poids, l’ouvrier insuffle dans le four environ 30 litres d’air toutes les 10 secondes. Quand la réduction
commence à s’opérer, on charge la cuve avec le minerai. Le refus s’écoule par deux orifices ménagés sur les petits côtés de la cuve. Il est plus riche en fer que beaucoup de minerais employés en Europe. La réduction dure de cinq à six heures. On démolit les parois de la cuve après avoir éteint te foyer avec de l’eau et on retire un lingot de 100 à 150 kilogrammes, que l’on débarrasse à coups de piques des parcelles de charbons adhérentes et qu’on envoie à la fonderie. Là on le brise en petits morceaux qu’on martèle au rouge pour en faire des lamettes du poids de 200 kilogrammes. Ce martelage est fait par des enfants ; j’en ai vu un qui n’avait pas dix ans. L’enclume est une espèce de tête de clou ayant 10 centimètres de diamètre. Voilà toute la métallurgie des Cuys : c’est ainsi qu’ils préparent un fer supérieur au nôtre. Preuve que quand le minerai est manganésifère, qu’il né renferme ni soufre ni phosphore, la vieille méthode catalane est encore la meilleure.” 

[“On a​clay area slanted in the shape of a donkey’s back, they build, with the yellow clay which abounds in the country, a rectangular box of 2.5 meters by 1.2 meters, in which they spread alternating layers of small grain ore and charcoal. Combustion is activated by two discontinuous blowers placed on the long sides of the tank; around ten clay pipes direct the air into a clay container whose movable upper wall is formed by a deer skin; by lifting this skin and compressing it under his own weight, the worker blows into the oven approximately 30 liters of air every 10 seconds. When the reduction begins to take place, the ore is loaded into the tank. The waste flows through two holes on the short sides of the tank. It is richer in iron than many ores used in Europe. The reduction lasts five to six hours. Then, they demolish the walls of the tank after having extinguished the hearth with water, and remove an ingot of 100 to 150 kilograms, which they free of the adhering particles of coal with spades, and send to the foundry. There they break it into small pieces which they hammer when red hot to make strips weighing 200 kilograms. This hammering is done by children; I saw one who was not ten years old. The anvil looks like a nail head 10 centimeters in diameter. This is the whole metallurgy of the Kuy people: this is how they prepare an iron superior to ours. Proof that when the ore is manganese-loaded and contains neither sulfur nor phosphorus, the old Catalan method is still the best.”]

[ADB Input: The ​“Catalan method”, or haizeola in Basque, is an iron-making process known in Southern Europe since at least the 9^th century, and was probably in use at the time of Angkorean peak. According to Mercedes Urteaga, Xabier Alberdi, Iosu Etxezarraga, Fernando Martín Suquía, Mertxe Urkiola and Jose Luis Ugarte’s ​“The haizeola and the origins of the ​‘Catalan method’: The medieval iron metallurgy culture in the Pyrenees”(Archeologické rozhledy LXX – 2018, 13 p.), ​“the incorporation of water wheels and waterfalls must have begun in around the 11^th century, although it seems to have spread and become more common place later, in the 13^th century. The application of hydraulic drive power made it possible to increase the injection capacity in furnaces and the furnaces to increase in size. In this new technological context, installations came down from the mountains and were located next to rivers.”]

Quality

“Le fer que les Cuys, peuplade tributaire du Cambodge, préparent au moyen de la méthode catalane, est fortement aciéreux. Avant [traitement], il possède une grande élasticité. On a constaté aux ateliers de l’artillerie, à Saigon, qu’il supporte cinq torsions d’équerre avant de se rompre. Encore est-il grossièrement martelé. Quand il aura subi la préparation convenable, sa résistance croîtra en raison de sa pureté. La trempe lui donne une dureté incroyable. On a constaté également qu’un ciseau, fabriqué avec le fer des Cuys, pénètre sans la moindre difficulté dans le fer doux importé de France. L’élasticité du fer de Compong-Swai est accompagnée d’une sonorité comparable à celle de l’alliage des cloches. Ce fer, qui est fabriqué en très petite quantité par quelques sauvages, se vend fort cher au Cambodge; on l’achète par lamelles d’environ 200 grammes, qui coûtent, la pièce, une ligature (environ
75 centimes). Cela porte le prix du kilogramme à plus de 3 francs. Aussi les Cambodgiens en sont-ils très avares.”

[“The iron that the Kuy, a people tributary to Cambodia, prepare using the Catalan method, is highly steely. Before [treatment], it has great elasticity. It was noted in the artillery workshops in Saigon that it withstands five square twists before breaking, even then it is roughly hammered. When it has undergone the appropriate preparation, its resistance will increase due to its purity. The tempering gives it incredible hardness. It has also been noted that a chisel, made with Kuy iron, penetrates without the slightest difficulty into the soft iron imported from France. The elasticity of the Compong-Swai iron is accompanied by a sonority comparable to that of the bell alloy. This iron, which is manufactured in very small quantities by a few savages, sells very dearly in Cambodia; it is purchased in strips of around 200 grams, which cost a ligature (approximately 75 centimes) per piece. This brings the price per kilogram to more than 3 francs. So the Cambodians are very stingy with it.”