The purpose of this study is to investigate on the structural properties of stone chambers distributed in Gyeongju and the excavated artifacts to examine the social aspect of the time when the stone chamber tombs were built. First of all, for the structural properties of the stone chambers, the plane form, the actual size, the location of the tomb entrance passage, the corpse base, and the morgue were examined. The structural properties of stone chambers were found to be related to the social status and position of the buried person, rather than the temporality. Therefore, the stone chambers in Gyeongju were classified into tunnel entrance style and horizontal entrance style chambers, and four types were set up according to the actual size, which represents the hierarchy well. Afterwards, the structures and the excavated artifacts of each type were reviewed to examine the characteristics and natures. In addition, since the differences and characteristics seen in each type are indicative of hierarchy, they were linked to the bone-rank system, the Silla caste system.
For type I, the plane form was found to be square, the location of the tomb entrance passage was at the middle, and processed stones were used for the morgue. It was found that these structural properties were unique to type I and it could not be seen in other types. For type II, the central tomb entrance passage could not be used, only the tomb entrance passages in the left and right sides were available, and the morgue made of processed stones could not be used. Type III was similar to type II and the natural stones were used more frequently for morgues. Type IV included stone chambers with horizontal entrance, and a part of the morgue was constructed using natural stones.
There were also differences in the funerary artifacts of each type. In type I, the artifacts that were not buried with the corpse in other types, such as gold earrings, gold belt hook, bronze twelve zodiac animal deities, burial mound figures were buried with the corpse, so it was found to be the tomb of the highest social class at the time, and it was possible to speculate on their lifestyles and social changes.
As such, from the structures of each type and the differences of the funerary artifacts, it was found that there were classifications and regulations of hierarchy and status in constructing the Silla stone chamber tombs. The archaeological data that can demonstrate the hierarchy seen in each type were the buckle accessories, which was applied to the 『Samguk sagi』 「Saekbokjo」's belt wearing regulations and associated with the status. Silla, a hierarchical society, stipulated that buckle accessories are to be worn with different quality of the materials depending on the head ranks. Gold buckle accessories in type I, black lacquered bronze buckle accessories in type II, and bronze and iron buckle accessories in type III~IV were identified, indicating some consistency with Samguk sagi's record. Based on these findings, type I was classified into the royalty and the nobility, and type II into 6~5 head ranks, types III~IV into 4 head ranks to commoners, and they were linked to the bone rank.