The stone of Son Bhandar is also much less hard than the granite of the Barabar caves, and therefore did not require the same degree of effort and technique.

[4] An inscription in the rock at the entrance of the cave in Gupta characters of the 4th century CE mentions the construction of the cellar by a Jain Muni ("Monk") named Vairadeva.

:[4] Muni Vairadeva, the jewel among the acaryas and of great lustre, caused to be made the two auspicious caves which are worthy of ascetics and in which were placed the images of arhats (ie tirthankaras)According to Gupta, however, this inscription may be ambiguous and, for him, might only mean that the cave was the subject of re-development work at that time.

[4] Le Huu Phuoc also entertains the possibility, to challenge the traditional idea that stone mirror-polishing techniques were imported from the Near East.

[3][7] The Chaumukha (quadruple) idol discovered inside the cave has a domical top and the stele on each side shows a dharmachakra.