Friday, March 24, 2006

Metallurgy, Southeast Asian (Glossary)

Southeast Asian metallurgy has been a source of controversy since the early dating of metal technology in places like Ban Chiang and Non Nok Tha in Thailand.

Thermoluminescence dating of pottery associated with eight bronze bracelets discovered by N. Suthiragsa revealed dates between 5000 and 4500 BCE. Radiocarbon dating of separately excavated bronzes uncovered by C.F. Gorman and P. Charoenwongsa gave dates of about 3600 BCE.

Such early datings for bronze technology exceeded that found elsewhere in the world and caused much commotion when first revealed. Joyce White who worked on Gorman's sites after the latter's death, found that the early dates were not "archaeologically meaningful." Her "re-analysis" of the radiocarbon findings pushed the date forward to 2100 BCE, based on the explanation that the bronzes may have been 'cut down' to lower levels than their true age.

However, it must be said that prior to the startling early data, the excavators apparently saw no problem with the strata and approved tests. Also, White's reanalysis can only apply to the radiocarbon dates and not to the direct thermoluminescence findings.

Recent discoveries at Balobok Rockshelter in the southern Philippines have unearthed early Neolithic tools dated to 5340 BCE and a bronze adze from a layer at 3190 BCE.

Early finds from Thailand reveal the use of four metals in local bronze work: copper, tin, arsenic and lead. The last three metals, each combined with copper to make bronze, are found naturally together with copper ores at worked sites near Ban Chiang and Non Nok Tha. So it would be rather simple for the blacksmith to accidentally or experimentally combine the metals and realize the superior resulting product.

Linguistic evidence

Probably even more controversial than the archaeological evidence is the suggestion by Robert Blust in 1976 that Proto-Austronesians dating from the period 5000 to 3000 BCE had a "knowledge of iron."

He states "the probability is small that a collection of unrelated bypotheses will provide a more plausible explanation of these facts than the single hypothesis that iron was known and worked at an early date, perhaps as early as Proto-Austronesian times." Although Blust in 1999 notes that words for metal do not necessarily require knowledge of metallurgy, we cannot dismiss the idea simply due to the negative archaeological evidence.

Iron was reconstructed as *bariS and further reconstructions were given for words such as "blacksmithing" and "anvil," the latter two terms restricted to Western Malayo-Polynesian. Using Solheim's chronology at least, this could fit well with the evidence of bronze at Balobok by 3190 BCE.

Admittedly though, no archaeological evidence has yet been found to support such an early iron-working hypothesis.

Fired pottery and the development of metallurgy

Evidence for pottery kilns predates that of metal working and it may be that the latter owes its existence to the former.

Hoabinhian culture in Vietnam began a process of firing clay pottery starting possibly as early as 10,000 BCE. At Shiweishan and Chenqiaocon near present-day Xiamen, clay pots were fired to about 680 degrees C. around 5000 BCE. At Ban Na Di in northern Thailand, pottery was fired to temperatures of 950 degrees C, and high-fired pots are associated with bronze finds near Hong Kong.

Early dates for high-fired pottery present development stages that could have led to experimentation with metal smelting.

Tools of the trade

Clay-lined furnaces were popular in the Southeast Asian region, and in some areas portable chimney furnaces were used.

Moulds were often made using the lost wax method in which a model of the desired object is first made with beeswax. The model is then covered with clay and baked, hardening the clay into a mould and melting the wax.

The magnificent Dong Son drums required a complex alternating clay and wax mould-making procedure that many believe required a trained full-time bronze specialist workforce.

Piston bellows

Although evidence of ancient bellows is lacking, in historical times, piston bellows have been the signature technology in Southeast Asian blacksmithing.

Piston bellows, the fire piston and the blowgun are related Southeast Asian technologies that rely on the principle of compressed air.

A sumpak (right) or fire piston of carabao horn and silver for lighting fires, and a kalikot (left) for grinding betel nuts made of ebony and silver, both from the Philippines and utilizing the principle of air compression. (Source: Conrado Benitez's History of the Philippines)

Possibly the blowgun was the first of these devices. In areas where no metal technology is present, the weapon is constructed from two strips of wood cemented together and wrapped with bark. Where metal is available, a metal rod is commonly used to bore through solid wood.

Frequent use of the blowgun will soon lead to the realization that the compressed air within the tube generates heat.

Piston bellows in Southeast Asia and Madagascar are made of bamboo or wooden tubes usually with feather-covered pistons on the end of a plunger. A "double-action" piston bellows normally involves two tubes worked alternately with each hand. As the plunger is pushed down the cylinder, the air is forced through a tube into the furnace. Upon reaching the end of the cylinder, the feathers collapse allowing the plunger to rise back without effort.

By working one piston at a time, a constant flow of air is introduced into the furnace.

Carving from Candi Sukuh in Java dating from the early to mid-1400s showing a smith forging a kris to the left, and a helper working a two-handed piston bellows to the right. (Sourc:

Development of the cannon

The earliest mention of possible military use of cannons may be that John de Plano Carpini who tells of a battle during the time of Genghis Khan, i.e., before 1227. The Mongol leader sent one of his sons to fight against Prester John, the king of "Greater India," a location which as we discuss in his blog is rather vague.

From thence the Mongol army marched to fight against the Christians dwelling in the greater India, and the king of that country, known by the name of Prester John, came forth with his army against them. This prince caused a number of hollow copper figures to be made, resembling men, which were stuffed with combustibles, and set upon horses, each having a man behind on the horse, with a pair of bellows to stir up the fire. When approaching to give battle, these mounted images were first sent forwards against the enemy, and the men who rode behind set fire by some means to the combustibles, and blew strongly with their bellows: and the Mongol men and horses were burnt with wildfire, and the air was darkened with smoke.

--- The Travels of John de Plano Carpini and other Friars, sent about the year 1246, as ambassadors from Pope Innocent IV, to the great Khan of the Moguls or Tartars

Some scholars have speculated that the hollow figures stuffed with combustibles might refer to small portable swivel guns like the lantaka.

Another possibility is something similar to the modern sumpak made by village smiths in the Philippines. The sumpak has the same name as the earlier fire piston and is similar in design relying on air compression using a plunger to ignite a shotgun-like shell. The age of this design is questionable but it makes sense that early cannons could have been derived from the fire piston. Both fires pistons and piston bellows were found in Madagascar but not the cannon, so the former are probably earlier inventions.

It is known that the Chinese had early knowledge of gunpowder and cannon-like devices. The medieval Arabs knew of saltpeter, the most important ingredient in gunpowder, as "Chinese snow," while the Persians called it "Chinese salt." According to Needham, the oldest cannon artifact is a bronze bombard at the Peking Historical Museum dated by inscription to 1332.

However, there is significant difference in the methods used by the Chinese to obtain saltpeter, as compared with those found in Southeast Asia.

In China, saltpeter is found on certain nitrogen-rich soils where winds from Eurasia helped dry decomposing organic material. In many areas, saltpeter crystallized on the soil surface especially during winter. The Chinese method was to inject urine into such soils to enhance the saltpeter formation.

Such methods were followed by the Arabs and Europeans. In Europe, beds of manure and other decomposing materials, were mixed with soil and ash and charged with urine.

Southeast Asians, on the other hand, appear to have used guano as their main source of saltpeter in contrast to the Chinese methods.

"This island [Mindanao], like the rest, is lacking in saltpetre, but the fault is remedied from the deposits of the giant bats (Murcielagos) which congregate in dark caves where they deposit an abundance of excrement which is made a substitute for saltpetre: and to this end there follows the labor necessary to extract the elements required for the manufacture of gunpowder, which is one of the most important needs of the islands. But although they succeed, the quality is not as quick on account of the moisture nor as powerful as ours. The matter of its manufacture has been brought to the notice of his Majesty as being more expensive and impracticable for the needs of the government."

(Mindanao and the Sulu Archipelago, by P. Francisco Combes, 1645, abridged translation. Original Spanish: "Falta en esta Isla el salitre, como en las demas deste Archipelago; pero suple su falta el Mindanao con otra mina que dio la naturaleza en unas grutas, y cueuas grandes, guarida de los murciegalos, que los ay mayores que una gallina, y en numero inmenso, que a no ser negras auroras de la noche, pudieran introduzirla en lon mejor del dia, segun assombra los ayres su multitud, ocupando muchas horas su negro exercito en la mancha, que a puestas del Sol ordena en busca del sustento. Estos como enemigos de la luz se acogen de dia al assilo de last tinieblas, que reynan en las grutas, con que les dexan abundancia de exrementos, los quales beneficiados se sustituyen al salitre; y al fin llega a conseguir el trabajo industrioso los ingredientes necessarios para la poluora, que es le mayor necessidad destas islas. Pero aunque salen con ella, ni es tan prompta, por ser naturalmente mas humeda, ni tiene la violencia que la nuestra. Por lo que, aunque muchos han presentado este arbitrio a su Magestad, nunca se ha aceptado, por ser de poco efecto, y de mayor gasto que el ordinario, y practiable para pocas cantidades, y no para la grandeze de los abastos Reales.")

"The process of manufacturing saltpetre and gunpowder will demand a short account. Saltpetre is obtained by boiling the soil of caves frequented by bats and by birds, chiefly swallows. This soil is decomposed dung of these animals, which commonly fills the bottom of the caves to the depth of from four to six feet."

(History of the Indian Archipelago : containing an account of the manners, arts, languages, religions, institutions, and commerce of its inhabitants, by John Crawford, 1820)

Nowhere in his vast work does Needham mention the use of guano, bat or bird dung, in making saltpeter.

Interestingly, guano, sulfur and charcoal, the three ingredients used in manufacturing gunpowder, occur naturally where volcanoes coincide with caves for bats and swallows. Such areas are, in fact, quite common in Southeast Asia.

In Medieval Technology and Social Change Lynn White, suggests that the cannon was developed through the concept of the blowgun imported by Arabs from Southeast Asia.

She states that Tamil sungutan and Malayalam tumbitan, both meaning "blowgun" are derived from the sumpitan "blowgun" of Insular Southeast Asia.

The Arabic zabatana and zabtaniya "blowgun" are traced to the
same source, and these also became names for the Arab arquebus.

From the Arabic derives the Italian name for blowgun, cerbottana, which by 1440 also is the name of a long-barrelled, small-bore cannon.


European explorers found excellent weapons known as lantakas used in Southeast Asia in the late 1400s and early 1500s. Mounted on a swivel yoke, the portable lantaka was most often suspended on stirrups attached to the rail of a ship. The setup allowed for recoil and quick, versatile aiming.

Most lantakas were made of bronze and the earliest ones were breech-loaded. During colonial times, there was a trend toward muzzle-loaded weapons. Europeans hired local smiths and also cast their own lantakas for use on their ships. The most impressive were the large double-barrelled lantakas. Small cannonballs or grape shot were fired from these weapons.

Double-barrelled lantaka from the Museo d'Arte Orientale. (Source:

Lantaka with swivel mount clearly displayed. (Source:

Larger culverin-like weapons, often made of iron, were also cast like the 17-foot cannon of Manila's Rajah Soliman. An indigenous type of arquebus, sometimes made of copper, is also frequently mentioned.

Despite the high-quality of their weapons, most kingdoms in Southeast Asia at the start of the colonial period had only small inventories. Problems procuring iron, and long rituals involved in producing weapons will be discussed below. Tome Pires was impressed with the artillery and firearms possessed by the Vietnamese empire, and their skill in using these weapons. However, even here Vietnam was forced to import most of its saltpeter and sulfur from places like Solor in eastern Indonesia.

As most of Southeast Asia lacked dry season winds such as those found in India and China, guano tended to be very moist compared to that found in Peru and other locations. The process of extracting saltpeter from guano thus was lengthy and expensive.

Iron technology and the Kris

The oldest dates for iron in Southeast Asia are from Ban Chiang going back to 1600 BCE. Again these are a source of controversy like the bronze datings.

Other early dates for iron can be found at Sa-Huynh sites in Vietnam.

Meteoric iron may have been preferred because of its supposed spiritual qualities as a 'heavenly metal.' The taste for meteoric iron may have even hurt local iron mining efforts. When Europeans came to the Philippines iron was valued higher than gold or silver, although they were well aware of the prices for these metals in other countries.

Kris manufacture throughout Southeast Asia involved the heavy use of meteoric metals. The kris was first and foremost a spiritual and ritual amulet as much as a battlefield weapon. The early high quality armament of the Shang dynasty in China was also made of meteoric metal.

Alternating "soft" and "hard" layers were folded in making the kris, with the hard layers involving iron, nickel and titanium, at least one of which and preferably all of meteoric origin. The soft layers were made of ordinary iron. Many modern kris makers (empu) however, use industrial metals to make their weapons.

The Wonotirto meteorite of 2001 in Java was found to have a high titanium content. X-ray fluoresence testing indicated that the stone was primarily titanium mixed with nickel, manganese and iron. (Source:

A high quality kris involves hundreds of laminations, and the best quality might involve thousands of layers.

While some kris may be highly-polished, the more characteristic technique is to create a rough finish known as a pamur. The kris is described as a three-edged weapon with the rough pamur side complementing the normal edges. An empu will often make cuttings to expose veins, considered to have special spiritual power.

After a bit of polishing, acidic solutions, including lime and arsenic, are used to pickle the blade to help prevent rusting. The arsenic blackens the iron and steel allowing the nickel and other impurities to shine through and give the pamur appearance. Etchings are also made using arsenic. The kris is then dryed over charcoal and incense and finally lubricated with scented oils.

The pamur of the kris is clearly displayed in this image. (Source:


Sacred smith

The smith has been studied in world cultures and most often the position is either highly-regarded or despised. In some cases, castes and taboos arise with particular reference to the blacksmith.

In India, for example, metal-working is most closely associated with the tribal peoples, particularly those of the Vindhyas. Iron is considered the metal of the sudras, or lowest caste, while copper was assigned to the highest caste brahmins.

Iron tools were forbidden in Ancient Greek temples, and the Roman priests of Jupiter used bronze and avoided iron tools for cutting their hair and nails. This prohibition was passed on to the Frankish kings.

African society is nearly divided between pastoral peoples, particularly those who ride the horse, who hold the blacksmith as a pariah caste, and settled agricultural people who elevate the smith to nobility, priesthood and royalty.

Turko-Mongol peoples generally revered the blacksmith and two of their greatest heroes Temujin (Genghis Khan) and Timur both had names derived from the word for "blacksmith." The Ghuz Turks in particular where considered practically a blacksmithing people en masse at one time.

On the other hand, from Nepal to Tibet the blacksmith generally has the same low position as in India.

"Blacksmith" itself denotes a low status, and in medieval Europe the work was often assigned to semi-nomadic Gypsies.

Southeast Asian cultures generally fall into the category of cultures that revered blacksmiths, and placed iron very high if not at the top of the metal hierarchy. In old Java, the terms empu or kyai "lord, master" referred specifically only to the iron smith or later to the weapons-maker.

A prince who was not in the line of succession could favorably consider becoming a blacksmith in the region from Java to Mindanao in old-time culture.

Blacksmith shops acted also as communal meeting places and even temples, and the blacksmith often held an hereditary chiefly position in the community. Only the high nobility maintained their genealogies as carefully as the blacksmith.

Because the weapons of the smith were often considered also as sacred heirlooms and at times even the domains of one's ancestors, the forging process was particularly painstaking in detail. The master smith awaited special astrological conjunctions and signs to undertake each stage of the weapon-making process.

In some cases, a very precious kris could take many years or even the entire lifetime of the smith to complete.

A Maranao sultan's betel box with silver applique (above). Below is a betel box with silver inlay and strap. The Maranao were skilled silver and goldsmiths and even practiced their own indigenous form of dentistry. Gold teeth were implanted by cutting away the tooth, allowing the pulp to dry, and placing a silver core in the cleaned socket. A gold exterior was welded to the silver nail.(Source:

Paul Kekai Manansala


Blust, Robert A. "Linguistics versus archaeology : early Austronesian terms for metals," Archaeology and Language, 1999, pp. 127-143.

Combes, Francisco. Historia de Mindanao y Joló: por el p. Francisco Combés ... Obra publicada en Madrid en 1667, y que ahora con la colaboración del p. Pablo Pastells ... sanca nuevamente á luz W. E. Retana, Madrid: Viuda de M. Minuesa de los Ríos, 1897.

Higham, Charles. The Archaeology of Mainland Southeast Asia, New York: Cambridge University Press, 1989.

___. The Bronze Age of Southeast Asia, Cambridge University Press, 1996.

Kerr, Robert. General History and Collection of Voyages and Travels: Arranged in Systematic Order: Forming a Complete History of the Origin and Progress of Navigation, Discovery, and Commerce, by Sea and Land, from the Earliest Ages to the Present Time, W. Blackwood and T. Cadell, 1824.

Needham, Joseph, Science and Civilization in China Volume V Part 2 Chemistry and Chemical Technology..., Oxford University Press, 1974.