Friday, April 10, 2015

Archeology Analysis of the Three Kingdom Period

Lauren Glover, PhD candidate in Archaeology at the University of Wisconsin-Madison, gave a Fulbright presentation entitled "All That Glitters Is Not Gold: Bronze and Stone in the Three Kingdoms Period". The write-up for her presentation is as follows: 
"During the Three Kingdoms period (300-668AD), various regions in South Korea were divided into several kingdoms, each with its own unique decorative style, but while divided, they were united by the heavy trade they transacted with each other, China, and Japan. This time period is extremely important because within it classical aspects of Korean culture were established that influenced later social, political and ideological developments, such as the use of bronze for rituals. Bronze and stone ornaments, especially in the form of jade, were important items to the elites of these kingdoms and were used for both displays of wealth and legitimacy, and for the ideological rituals required to maintain control in both the physical and spiritual world. Elites continued to use bronze and stone even when more economical, practical and prestigious options were available such as gold, iron and glass. This suggests that the materials themselves had significance to Three Kingdoms period people which could not be fully divorced from mundane issues. I am especially interested in tracing the manufacture and use of gokuk 곡옥 (curved beads) during this period since they were used specifically by elites in unique displays of wealth, power and ideology. 
"My research objective is to use a combination of new and traditional analysis to learn the “biography” of an artifact from raw material to final deposition. I utilize an XRF (X-Ray fluorescence) scanner on both bronze and stone to determine a rough composition of the artifact. The compositions are used both in lead isotope analysis and in determining the origin of the stone artifacts. An extremely new method of lead isotope analysis called EDTA (Ethylenediaminetetraacetic Acid) solution analysis is also being utilized. All other methods of lead isotope analysis require harming the artifact so using this method has allowed me to analyze artifacts which would otherwise not be examined. The results of the lead isotope analysis will be compared to lead isotope ratios across East Asia to determine where the copper in the bronzes was coming from. I use silicon impression material to take impressions of the holes in the ornaments (usually beads). Those impressions will eventually be scanned with an SEM (scanning electron microscope) to determine what type of drill was used and if there is any wear on the inside of the hole. Until then, I use a digital microscope, a scanner, and my own measurements of the beads to look for patterns in manufacturing methods and style in the hopes of identifying specific groups of people or workshops that were dealing with creating these ornaments. I also hope to use the data from this project to replicate artifacts in the future in order to learn more about the manufacturing process."
Lauren Glover will be doing the first half of her research here in South Korea and the second half in Japan, both of which times she will be examining bronze and stone used ceremonial during the span of the Korean peninsula's Three Kingdoms period.

Research Objectives: Biography

  • To determine the "biography" of bronze and stone artifacts from raw material to final deposition
  • To use this biographical information to learn more about power, religion, and economy during the Three Kingdoms period 
  • Gosden and Marshall (1999) idea of biography: "As people and objects gather time, movement and change, they are constantly transformed, and these transformations of person and object are tied up with each other."

The National Research Institute of Cultural Heritage makes statements that the gilt bronze shoes were made in the Baekjae Kingdom. Such a finding offers a glimpse into the relations between Baekjae and the native forces of Mahan (1st C BC - 3rd C AD), an ancient kingdom that was later absorbed into the Baekjae Kingdom. - Source

I believe these are the gilt bronze shoes that were discovered still having human bone in them and which are housed in the Baekjae Museum. Finding bone is a rare find in the Korean Peninsula because Korean soil is very acidic so bone easily perishes, as acid destroys organic material and therefore there is little carbon in the soil
... which ultimately messes with carbon dating also.
Research Objectives: Understanding Trade and Trade Routes

  • To develop new, area specific models of regional and interregional trade and exchange
  • Uni-directional model: that goods and culture flowed from China, through the Korean peninsula (without being influenced by Korean culture) and on to the Japanese archipelago
  • My model: inter- and extra-regional with bi-directional exchange of goods, ideas, people and technology

What we know about trade:

  • People have been trading between the Russian Far East, northern China, the Korean peninsula, and the Japanese archipelago for the past 25,000 years
  • Yellow Sea Interaction Sphere 500BC - 500AD (Barnes 1999): goods, ideology, technology
  • Tomb styles and pottery are well studied during this period
  • Historical texts list a number of items and services being traded, only some of which can be verified archaeologically

Already a lot is known about trade so Lauren Glover will be looking specifically at bronze and stone which hasn't been highly researched.

Power and wealth:

  • Wealth communicates status, legitimacy, ideology and power (Baines and Yoffee 2000, Kenoyer 2000)
  • Value in archaeology:
    • "situationally mediated" (Appadurai 1886, Kenoyer 2000)
    • rare materials more valuable
    • the more labor invested in an object, the more valuable it is
    • objects gain value the more technological processes or knowledge is needed to create them
    • valuable symbols of wealth will be controlled by elites

The Three Kingdoms Period:

Actually the Three Kingdoms period should really be considered as the Four Kingdoms period as Goguryo (37BC - 668AD) was usually at war with the three southern kingdoms, which definitely had some or even a lot of influence on the culture and trade of the southern kingdoms.
Mumun Period: 1500BC - 300BC
Proto 3 Kingdoms Period: 300BC - 300AD
3 Kingdoms Period: 300AD - 668AD
Unified Silla: 668AD - 935AD
Map of the Three Kingdoms of Korea, at the end of the 5th century - Wikipedia

During the Three Kingdom period, gokuk (curved beads) were in great use. The Shinto religion in Japan was probably derived during this time, and jade became popularized.

But why bronze?

Although the common copper alloys are often all called "bronze", in fact, the different combinations of copper + alloy produce different metals (refer to picture on left).

Copper + zinc making brass wasn't in use in the Three Kingdoms period because zinc was harder to isolate and this isolation process didn't happen until much later.

However, iron was used in the period. Iron was easier to work with, cheaper and more durable than other options. Tin was still expensive and only used by the elite classes, but it could be exported from China. When worked with copper, the two metals created bronze which is very bright and like gold when it is new. If a lot of tin was used, the better the reflection in the finished product. Also, if a lot of tin was used, the resonance of the bronze would be better, for example, bronze bells with more tin had more resonance and tone.

The military also used bronze for their armor or equestrian equipment, e.g. stirrups, but if used, this type of bronze was gilt bronze. Military headgear, spears, halberds, daggers, buckles, etc were also items popular for the elite soldiers.

Testing Methods

Lauren uses the X-ray florescence (XRF) measure for ascertaining the metal of the object. There are hand-held and larger, heavier types but the method is the same. Shoot the beam which penetrates a few centimeter and throws waves back. The point is to get a lead reading for a lead isotope analysis. With this analysis, it is possible to know where the lead is derived from -- which quarry or mine, whether within Korea or China or wherever. Often this is not a useful method for isolating location of lead origin; however, in Asia (China, Korea, Japan) the lead isotopes are very different, hence this method is very revealing as to trade relations and political and social interactions of the period.

Another method, Lead Isotope Provenancing or is it EDTA (Ethylenediaminetetraacetic Acid, is to soak the artifact in a solution from 20-60 minutes and traces will break off into the solution, which is then sent off for analysis. This is a very non-invasive method as opposed to using a laser which leaves a tiny pit or even the more damaging method of shaving a small bit off (damaging) and analyzing the shavings. Lauren proposed taking many samples using this non-invasive method, but gaining access to ancient artifacts takes time. As of now, she has run five tests, and four of them appear to fall within the Korean lead isotope areas.

Gokuk 곡옥 (curved beads)

Gokuk are made from every material possible (clay, stone, amber, jade ...) and are found on head pieces, earrings, around people's necks in both Korea and Japan. Although from these instances they would seem to be ornamental for people's bodies, their uses are thought to be much more extensive. The trouble with defining their uses, however, is that most typically they are found disconnected from their associated object of use in tombs, in houses and campsites, so archeology can only make assumptions as their uses which extends beyond the elite classes. The five, arguably six, royal crowns discovered in tombs of the Three Kingdom period all had gokuk made of various colors of jade on them.

Crown, Korea, Silla Kingdom, second half of 5th century. Excavated from the north mound of Hwangnam Daechong Tomb. Gold and jade; H.10 3/4 in. (27.3 cm). Gyeongju National Museum, Korea, National Treasure 191
According to Lauren, during the Three Kingdoms Period there were no gokuk bead workshops on the Korean peninsula (although some/many had existed prior to the period but stopped producing for some reason). Many gokuk workshops were in operation in the Japanese archipelago at this time. The ritual beads found on royal crowns were of jade, but jade needs to be qualified as there are the "jade" beads made of jadeite and those made of nephrite. Both types though are very hard need a lot of work in their production.

Jadeite - very rare, expensive, only found in 10 places around the world (Japan, Russia, western Alps, California, Myanmar, Guatemala, Central Asia ...) 
Nephrite - not as rare or expensive, has a lot of variety, found around the world (Canada is the largest source)
Studying the beads is to study ritual symbolism and therefore to better understand religion, history and ethnography in order to form working hypothesis. Using Specific Gravity and XRF, Lauren analyzes the type of jade or nephrite and can ascertain in a large degree from where the stone originated from, and therefore make guesses on trade routes. 

Also studying bead production for its ceremonial or practical purposes, she analyzes the drill hole and threads the drill made. Drill holes tell stories of their own. By taking pictures with a particularly high-powered camera and which are then studied on the computer, she can ascertain the type of drill used to make the gukuk bores. She also studies the angles of the bores, whether the bores were made from one side or both and, if from both, how evenly or unevenly the drill patterns meet. The Scanning Electron Microscope (SEM) also comes in handy for understanding the sample's surface topography and composition.
  • metal drills make smooth bore holes
  • stone drills make uneven bores; some are tapered, others are cylindrical
  • copper drills make striations

Lauren is a PhD candidate in archaeology at the University of Wisconsin-Madison. She has a MA in Archaeology from the University of Edinburgh in Scotland, a MA in Japanese Studies from the University of Leeds in Britain, and a MA in Anthropology (Archaeology) from UW-Madison. Lauren studies the trade, exchange and manufacture of bronze and stone ornaments in the Korean peninsula and the Japanese archipelago from 250-668AD. She is also interested in mortuary rituals, ideology and religion, experimental archaeology, gender, and nationalism. Feel free to visit her website:

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