Stoneware ceramics produced with iron-rich clay bodies and translucent blue-green glaze were manufactured in the Korean peninsula beginning in the 10th century and reached technical maturity during the Goryeo dynasty (918 to 1392 CE), at which point they surpassed in quality the Chinese wares that had originally inspired their production. The glaze color, called bisaek in Korean, meaning "the color of jade" or "kingfisher color," was achieved through a two-stage firing process involving a reduction atmosphere that produced a pale blue-green hue ranging from cool gray-green to deep jade. The term celadon itself is a French word of Greek derivation, coined in 17th-century Europe after the green cloak of a shepherd character in Honoré d'Urfé's pastoral romance Astrée, and was adopted into English usage during the 19th century. Korean potters and scholars use the term cheongja. By the 12th century, Chinese diplomatic envoy Xu Jing recorded in his official account Xuanhe Commissioner's Illustrated Account of Goryeo, compiled in 1123 CE, that Goryeo celadon techniques had become more sophisticated and the glaze more beautiful than its Chinese counterparts. The primary production centers were concentrated in the Gangjin region of South Jeolla Province and the Buan region of North Jeolla Province, both on the southwestern coast of the Korean peninsula. Gangjin remains the center of modern celadon production today. High-grade celadon was produced exclusively on royal commission for the Goryeo court. Lower-grade production served temples, provincial offices, and aristocratic families. In November 2025, the National Research Institute of Maritime Cultural Heritage recovered 87 bowls and cups from an underwater site off Taean, South Chungcheong Province, dated between 1150 and 1175 CE, in a preservation condition described by researchers as effectively 100 percent intact.


 Material and Craftsmanship

Korean stoneware fired at temperatures of 1,000 degrees Celsius or higher during the Three Kingdoms period (57 BCE to 676 CE) constitutes the earliest documented example of high-fired ceramics in the world, establishing a technical baseline that later enabled celadon production. Celadon production as a defined ceramic category began in Korea during the 10th century, stimulated by the arrival of Chinese potters who introduced Yue kiln technologies from Yuezhou county in present-day Zhejiang Province following political upheaval on the Chinese mainland.

Potters formed vessel bodies from iron-rich clay sourced from coastal deposits along Korea's western and southern coasts, particularly in the Gangjin and Buan regions, where the clay composition was uniquely suited to celadon production. The glaze was compounded from iron oxide, manganese oxide, and quartz particles suspended in a liquid medium and applied to the bisque-fired vessel body. The total iron content of the clay body and glaze, combined with firing conditions inside the kiln, determined the final color of the finished piece. Temperatures were maintained at or below 1,150 degrees Celsius during glaze firing. Excess iron in the clay or glaze, or incorrect atmospheric conditions, shifted the color toward brown or olive rather than the desired blue-green.

Chinese celadon was fired in brick kilns that allowed oxidizing atmospheric conditions during firing. Korean artisans used mud kilns built into hillsides, ascending structures approximately ten meters in length that more effectively blocked oxygen flow and produced a reduction atmosphere during the critical firing phase. A reduction atmosphere strips iron molecules in the clay and glaze of oxygen, shifting their chemical state and producing the characteristic cool blue-green tone rather than the warmer olive green of Chinese celadons fired under oxidizing conditions. The two-stage firing process required a bisque firing first to dry and harden the unglazed vessel, followed by glaze application and the final high-temperature reduction firing.

The signature technical achievement of the Goryeo period was the sanggam inlay technique, developed no later than 1157 CE based on excavated celadon roof tile fragments from kiln sites active during the reign of King Uijong (r. 1146 to 1170). The sanggam process required carving or stamping the desired design into the surface of leather-hard clay before the first firing. White slip, produced from refined white clay, was pressed into carved depressions to produce white inlay. Red ocher clay, which fired to black at kiln temperatures, was pressed into separate carved areas to produce the black components of the design. The three clay types used simultaneously in sanggam, the base clay, the white slip, and the red ocher, contract and expand at different rates during firing. Maintaining structural integrity across all three clay types through the heat cycle required the most advanced level of ceramic technology available in the Goryeo period. After inlay application, the entire vessel surface received a single coat of translucent celadon glaze before the final firing. The fired glaze, thin and translucent, allowed the inlaid white and black designs to show through clearly while simultaneously embedding them within the glaze layer, protecting them from surface wear.

Goryeo poet Yi Gyu-bo (1168 to 1241) documented the difficulty of achieving the bisaek color in his Collected Works, writing that blue ceramic cups were fired but only one in ten was kept, conveying that the rejection rate for pieces not meeting color standards was extraordinarily high. Firing a single successful batch of high-grade celadon at the technical standards demanded by royal commission required multiple attempts. This quality control, maintained throughout the 12th-century peak production period, accounts for the exceptional consistency of color across surviving royal-grade examples.

 Form and Features

The maebyeong is the vessel form most closely identified with Goryeo celadon in institutional and scholarly documentation. The maebyeong, called meiping in Chinese, is a tall vase that rises from a narrow base, expands to a full rounded shoulder, and terminates in a small circular mouth with a flat lip. Korean potters modified the Chinese meiping prototype to produce a rounder, more generously curved body by the early 12th century, differentiating the Goryeo form from its Chinese source. Recent archaeological evidence from underwater shipwreck excavations at the Mado sites off Taean has established that maebyeong vases served as containers for honey and sesame oil during transit, rather than purely as display vessels, as had been assumed in earlier scholarship.

Beyond the maebyeong, Goryeo potters produced bowls, dishes, cups, ewers, bottles, wine vessels, incense burners, cosmetic boxes, water droppers, pillow rests, censers, and architectural elements including roof tiles. Ceramic pillows were carved with lion figures supporting the sleeping surface. Incense burners were produced in the form of mythological creatures including a documented lion-shaped example now designated National Treasure No. 60, and a lotus-shaped example designated National Treasure No. 95 with an openwork perforated lid through which incense smoke exits. Ewers were produced in the form of Taoist monks and dragon-fish hybrids. King Uijong commissioned celadon roof tiles for an entire royal pavilion at the Goryeo capital of Gaeseong in 1157 CE, the same year that excavated kiln fragments establish the earliest confirmed evidence of the sanggam inlay technique.

A celadon maebyeong currently designated Treasure No. 1869 by the Cultural Heritage Administration of South Korea measures 30.3 centimeters in height, 5.3 centimeters at the mouth diameter, and 10.5 centimeters at the foot diameter. Its surface carries a cloud and crane inlay design executed in sanggam with white and black clay. Both the mouth and foot of the vase are encircled by a repeated abstract geometric motif, called the "lightning pattern" in informal usage, executed in black inlay. The composition integrates this geometric framing with the central pictorial field of cranes in flight among upward-pointing cloud forms. Scholars at the National Museum of Korea have cited this vessel as exemplifying the highest level of sanggam inlay production: consistent glaze color, precise inlay registration, near-complete surface preservation without scratching, and balanced compositional integration of the decorative field with the vessel's physical form.

 Function and Use

Goryeo celadon occupied two distinct functional categories that operated simultaneously and were understood within Goryeo society as mutually reinforcing rather than contradictory. The first was utilitarian: celadon vessels served as containers for food, drink, oil, honey, incense, and cosmetics across the entire Goryeo social hierarchy, from the royal court to provincial temple communities, differentiated by grade of finish and quality of production. The second function was cosmological and symbolic: the motifs, forms, and glaze color of celadon were understood to encode spiritual and auspicious content that made the objects active participants in the ritual and religious life of their users.

High-grade celadon was produced on royal commission and delivered to the Goryeo capital of Gaeseong as a form of tax tribute from the kiln centers of Gangjin and Buan. Transportation of celadon from production sites to the capital was conducted primarily by sea, along the western coastal route. The wooden tablets and bamboo tallies recovered from underwater shipwreck sites at Taean document in writing the origin kiln, destination recipient, and consignee for individual celadon shipments, providing the most precise logistical record of how Goryeo royal commission ceramics moved through the state supply system. The Mado Ship No. 2 wreck carried a bamboo freight tag identifying a maebyeong of honey and sesame oil addressed to Officer Oh Mun-bu of the Jungbang Council in Gaeseong. High-quality pieces were individually stored inside large protective jars lined with straw. Thirty to forty lower-quality pieces were stacked together and secured with straw rope for bulk transport.


Incense burners in celadon served specific liturgical functions in both Buddhist temple practice and in elite private household ritual. The perforated openwork lid, designed to release incense smoke through carved apertures, established celadon as a medium for sacred objects with direct ceremonial function. Celadon cups designated for use in Buddhist ritual tea ceremony were produced as dedicated liturgical objects. The tea culture that developed within Goryeo Buddhist monastic communities created sustained institutional demand for high-grade celadon teaware throughout the dynasty.

 Cultural Context

Buddhism was established as the state religion of the Goryeo dynasty from its founding in 918 CE, and the demand it generated for ritual objects, incense burners, tea vessels, and devotional wares formed the primary institutional market for high-grade celadon production throughout the dynasty's existence. Lotus motifs, which in Buddhist iconography represent the emergence of purity and enlightenment from impurity and attachment, appear across the surface decoration of celadon in incised, relief, inlaid, and openwork forms. Lotus petal designs cover the exterior faces of bowl bases, the shoulders of ewers, and the lids of incense burners as recurring structural motifs. Buddhist scholar Kyung Moon Hwang has written that the bisaek glaze color itself seems to evoke Buddhist spirituality, a quality recognized in the reception of the objects as much as in their overt iconographic content.

Taoism exerted parallel influence over Goryeo celadon's iconographic program, most directly through the crane and cloud motif that constitutes the most frequently applied decorative design across all surviving 12th-century inlaid celadon. Academic analysis published in the International Journal of Korean Art and Archaeology has established that the crane and cloud design appearing on Goryeo celadon of the 12th century derives from Taoist visual tradition representing the world of immortals. Taoist immortals in Chinese and Korean visual culture were conventionally depicted riding cranes through clouds, and the crane itself was identified as a sacred creature of the Taoist celestial realm. The clouds on documented maebyeong examples are shaped like upward-pointing flower forms, which scholars interpret as conveying a rising, ascending movement consistent with the Taoist aspiration for transcendence. King Uijong (r. 1146 to 1170), under whose reign the sanggam inlay technique reached its documented maturity, was a recorded patron of Taoist ritual institutions and commissioned dedicated Taoist halls for exclusive royal use. The concentration of Taoist imagery on the finest celadon produced during his reign reflects direct patronage alignment between royal Taoist practice and the iconographic program of royal commission ceramics.

The association between celadon's bisaek color and jade constituted a foundational premise of the ceramic's cultural status. Jade in East Asian material culture across China, Korea, and Japan encoded the virtues of purity, longevity, cosmic harmony, and proximity to the sacred. The Goryeo court's decision to call the celadon glaze color "the color of jade" in official documentation placed the ceramic within the symbolic register of the most culturally elevated material in East Asian civilization. This association was not decorative or incidental. It established celadon as a medium capable of carrying the cosmological weight previously reserved for jade objects, enabling ceramic vessels to function as containers for sacred ritual within contexts where jade had previously been required.

The adoption of white porcelain as the preferred court ceramic during the Joseon dynasty (1392 to 1910) reflected the shift from Buddhist and Taoist to Neo-Confucian state ideology. Joseon Confucian scholars associated the opulence and decorative elaboration of celadon with the Buddhism of the preceding dynasty. White porcelain, plain and austere, aligned with Neo-Confucian values of simplicity, moral discipline, and the rejection of sensory excess. Celadon production did not cease but was displaced from royal commission and declined in quality through the 15th and 16th centuries.

 Discovery and Preservation

The primary institutional repository of Goryeo celadon in Korea is the National Museum of Korea in Seoul, which holds the most comprehensive collection of documented examples including pieces designated National Treasure and Treasure status under Korean cultural heritage law. The Goryeo Celadon Museum in Gangjin, established adjacent to the historic kiln sites where the highest-grade royal commission celadon was produced, holds collections with direct provenance from the production region and maintains an annual celadon festival. Major international institutional holdings include the Metropolitan Museum of Art in New York, the Museum of Oriental Ceramics in Osaka, the Cleveland Museum of Art, and the Freer Gallery of Art at the Smithsonian Institution in Washington, D.C.

A significant portion of museum-held Goryeo celadon was recovered from royal tombs and palace site excavations rather than intact production or use contexts. Burial deposition of high-grade celadon alongside elite Goryeo dead was standard practice, and tomb context has preserved a disproportionate share of the most intact and highest-quality surviving examples. Mongol invasions of the Korean peninsula beginning in 1231 CE systematically destroyed production workshops in the Gangjin and Buan regions. When potters resumed work in the late 13th and 14th centuries following the end of Mongol occupation, the technical and material conditions supporting peak bisaek color production had been irreparably disrupted. The pale blue-green glaze of 12th-century royal commission pieces was replaced by a darker, duller green across all post-invasion production.


The underwater archaeological zone off the Taean Peninsula on Korea's West Sea coast has produced the most significant body of contextually documented Goryeo celadon recovered in the modern period. A local fisherman's accidental discovery of a submerged wreck in 2007, designated Mado 1, initiated systematic underwater survey of the area by the National Research Institute of Maritime Cultural Heritage. By November 2025, more than a dozen shipwrecks had been identified along the Taean coastal corridor. The most recent find, reported November 10, 2025, recovered 87 celadon bowls and cups dated between 1150 and 1175 CE from a site adjacent to the already-excavated Mado 4 wreck. The 87 pieces were recovered with an effective 100 percent preservation rate, their surfaces exhibiting glaze condition consistent with recent kiln production. Researchers attributed this to the dense clay-rich seabed sediment of the Taean tidal mudflats, which sealed the ceramics from oxygen exposure, wave energy, and biological activity. The site, informally designated Mado 5 pending verification, may represent the oldest shipwreck ever found in Korean waters if the hull structure, now partially identified through sonar survey, is confirmed. The wooden tags and bamboo tallies that accompanied celadon shipments in Goryeo-era state transport practice, if recovered from the Mado 5 hull, would identify the specific kiln of origin, the consignee, and the destination of the cargo, adding another documented entry to the logistical record of the royal celadon supply system.

 Why It Matters

Goryeo celadon documents a ceramic tradition in which technical mastery, state institutional demand, Buddhist and Taoist cosmological symbolism, and the cultural valuation of jade were integrated into a single production system sustained for over four centuries. The sanggam inlay technique, which required the simultaneous control of three clay types expanding at different rates through a reduction firing cycle, has no documented parallel in any other ceramic tradition of the same period and constitutes a technical achievement that was not replicated outside Korea. The documented rejection rate of nine out of ten pieces during peak royal commission production, recorded in a 12th-century literary source, establishes that the quality standards applied to high-grade Goryeo celadon were enforced through material loss at a scale that makes surviving royal examples statistically rare relative to the total volume of production. The ongoing recovery of intact celadon cargo from Taean shipwrecks, with the most recent find in November 2025 yielding 87 pieces at effectively complete preservation, continues to generate new primary evidence about the state logistics, distribution networks, and functional uses of celadon in the Goryeo period that cannot be recovered from tomb or palace excavations alone.