I wonder if it was bad luck to give a gift of knives in the Ming as it is today, and whether the Sultan had been so informed.
Hong-wu: Year 4, Month 8, Day 13
22 Sep 1371
The minister Yi-si-ma-yi, who had been sent by Ma-he-mo-sha, the king of the country of Bo-ni, presented a memorial and a salutory message and offered tribute of local products. Previously, the Emperor had ordered the Investigating Censor Zhang Jing-zhi and the Fu-jian Branch Secretariat Office Manager Shen Zhi, to go as envoys to this country. At this time, the king sent an envoy to accompany Jing-zhi and the others on their return and to bring tribute to the Court. He brought "he-ding", live turtles, peacocks, plum-blossom camphor, `rice' camphor , `sugar' camphor, Western Ocean white cloth, laka-wood, bees-wax and other products. His memorial was of gold and the salutory message was of silver. Both were engraved in fan script, similar to that of the Hui-gu. It was Imperially proclaimed that patterned fine silks and silk gauzes interwoven with gold thread were to be conferred upon the king of the country, while his envoys were to be given fine silks and other silks, as appropriate. Bo-ni is in the great ocean of the South-west and it controls 14 administrative divisions (zhou). It is subject to She-po, from whence it is a 45 day journey. It produces famous aromatics and exotic goods. The king had offered Jing-zhi and the others presents of gold waist knives, kapok (吉貝) and cloth, but the presents were declined rather than accepted.
Zhong-yang Yan-jiu yuan Ming Shi-lu, volume 3, page 1264_