Events/Artifacts (north to south) Events/Artifacts Artifacts The Butuan Ivory Seal or BIS is an ivory stamp or seal stamp or a privy seal associated with a Rhinoceros Ivory Tusk [clarification needed], dated 9th–12th century, was found in Libertad, Butuan in Agusan del Norte in southern Philippines.
[1] Another archaeological piece with ancient inscription, the Butuan Ivory Seal was recovered in the 1970s by pot hunters in a prehistoric shell midden site in Ambangan, Libertad, Butuan in Agusan del Norte.
[2] The ivory seal as well as other archaeological materials recovered in Ambangan archaeological sites are proof that Rajahnate of Butuan was an important trading center whose official seal marked the source of commodities it produced and exported.
[2] The innovation of substitution of phoneme /b/ with /w/ and sandhi of /wa/ equal of /u/ followed by /a/ can be found in Javanese,[3][4] thus the block [Bu][Tba][N-] related to Butwan and later Butuan.
Altogether, these data demonstrate that Butuan was a thriving international trading port a thousand years ago.