The fishermen after their diving operation collect the oysters on the sea bed. In the 6th Century A.D. , Cosmos Indico Pleusters( 530 - 550 A.D ), an Egyptian traveler, makes reference in his account to the chank and pearl market at Marallow, which has been identified with the chank and pearl fishery of the Ramanathapuram coast.

About the middle of the 9th Century, the Arab scame into contact with the pearl fishery of Ramanthapuram coast and had noticed the pearl and chank industries thriving well. Two of the Arab swriters Sulaiman and Abu Zaid have recorded that pearls were valued as greatest treasures by the local kings. During the 10th and 11th Centuries,the Imperial Cholas were in possession of the coast and there are no records to give authentic information on pearl Industry. Only a few of their inscriptions record grants of pearls to the temples.

During the period of the later Pandyas ( 12th and 13th Centuries ) the pearl industry in this region wasa flourishing one Marco Polo ( 1260 - 1300 ), who traveled in South India during this period, says in his account that the later Pandyas monopolised the pearl Industry and did not allow any one to take pearls out of the kingdom. He also gives a description of the pearl fishery in the Tamil Coast.

The speciality of the port at Kilakarai is that, the ships that are anchored here, were not disturbed by any means of wild wind or tidal waves. This is because of the natural surroundings of islands, and pits that were situated near the coast. The pits that were situated here, is the cause for the production of sea livings like Faura & Floras. Pearls were found near to the Uppu Tanni Tivu and in between the Nalla Tanni Tivu and the Annai Par Tivu. Thus merchants and labours here, are living in the natural surroundings.

It had been represented in 'The Travels of Marco polo' that " Leaving the island of Zeilan, and sailing in a westerly direction sixty miles, You reach the great province of Maabar ( Kayal )which is not an island, but a part of the continent of the greater India, as it is termed being the noblest and richest country in the world. It is governed by five Kings, of whom the principal is named Sendar-band with in his dominions is a fishery for pearls in the gulf of a bay that lies between Maabar and the island of Zeilan, where the water is not more than from ten to twelve fathoms in depth and in some places not more than two fathoms. The greater proportion of the pearls obtained from the fisheries in the gulf, are round of a good lustre. The spot where the oysters are taken in the greatest number is called Bertala, on the shore of the mainland, and from thence the fishery extends sixty miles to the southward ".

Traders from the Middle East Countries assembled in this port ( Kilakarai ) from very early times. Horses were imported in large numbers even by the Pandya Kings. Many Arabs settled down here.When Malik Kafur came to Rameswaram on his raid in 1311 A.D., he found a number of Arab settlements here. Even now Kilakarai is predominantly Muslim in population and there are a few very old mosques here.