In 1990, the National Museum of the Philippines in collaboration with World Wide First (WWF) conducted a shipwreck excavation at Pawikan Shoal, the southernmost atoll of the Kalayaan Group of Islands. The project led to the recovery of Chinese celadon and qingbai ceramics in the form of cups, bowls, saucers, and plates as well as stoneware jars. One jar was filled with 54 kilograms of bronze bracelets hidden under a layer of tea. These may have been purposely hidden as the Chinese imperial government during this time prohibited the export of metals. The Chinese ceramics have been dated to the southern Sung dynasty period (1127-1279). There were also glass beads, iron concretions, wood fragments, and a granite anchor stock, though no hull remains were found.