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First time the tomb was opened to take some earth to cure the son of ruling king Mahadevan. The sand from the tomb is believed to have  miraculous healing powers.
Between A.D. 220 and 232  a merchant called Khabin removed greater portion of the relics to Edessa in Asia Minor. Later this was moved to Chios island and finally to Ortona on the east coast of Italy.
A piece of bone and the lancehead that used to kill the saint, excavated from the tomb, is kept in a monstrance in the museum.

Marco polo visited the tomb in 1293 and recorded about the miraculous healing powers of the sand taken from the tomb.
Pilgrims used to take sand from the tomb back to their homes and keep it with devotion.
For the benefit of pilgrims Shrine is providing 'Relic Card' embedded with sand taken from the tomb.