Glaze can be divided into two groups depending on the melting temperature: low fire glaze that melts at temperatures lower than 900 degrees centigrade and high fire glaze that melts at temperatures higher than 1200 degrees centigrade. The glazed pottery that was baked for the first time in Japan used the low fire lead glaze. Although Nara Sansai (three-colored glaze pottery) is known as the representative pottery of this technique, it was already introduced into Japan in the seventh century, which was earlier than when Nara Sansai was produced. The earliest examples of this technique are said to be Ryokuyusen of Kawara Temple in Nara and Ryokuyukandai in the Tsukamawari tumulus.
In the Nara period, the production of the three-colored glaze pottery began in Japan inspired by To Sansai (three-colored glaze pottery of the Tang period) that had been introduced into Japan. While three colors of green, brown and white were initially used, they were gradually reduced to green and white and eventually to only green. In the Heian period, multi-colored pottery was no longer created and only the green glaze was used to copy the celadon of the Esshuyo kiln in China.
This green glaze four-legged jar was also modeled after the celadon of the Esshuyo kiln. While the original Esshuyo celadon jars were a small four-legged type, those baked by Sanageyo kiln in Japan were larger in size than usual. While the form of Nara Sansai jars, which are supposed to be a copy of To Sansai jars, shows more of the characteristics of the unglazed jars of the Nara period than those of To Sansai, this green glaze four-legged jar by the Sanageyo kiln takes a more relaxed form similar to that of To Sansai jars. It has three convex belts around the body and four perpendicular belts, the ends of which continue to the animal feet.
It is known that some green glaze four-legged jars were used as cremation urns and this jar may have been used as such. The green glaze develops into a bright color on the white pottery body, demonstrating Sanageyo’s highest technique in using green glaze.