When a prince of the Ming dynasty married, the royal court was expected to give a wedding gift. This gift included one gold ingot 50 liang (about 88 oz) in weight. Two such ingots were discovered in Prince Zhuang's tomb, indicating he had married twice. The inscription on one ingot indicates that it was made in the 14th year of the Yongle Emperor (1416). The inscription on the other ingot tells us that its gold did not come from China.
The gold in this ingot came from "西洋", the western ocean, a term used in Ming times to refer to areas to the west of the South China Sea, including the Indian Ocean and its surrounding regions. From the third year of the reign of the Yongle Emperor (1405) to the eighth year of the reign of the Xuande Emperor (1433), the Ming emperors sent out seven naval expeditions to the western ocean, lead by the eunuch Zhang He. These great fleets voyaged to Southeast Asia, South Asia, and even the coast of Africa, greatly enhancing exchanges between the Ming dynasty and the states in these regions.
The inscription on the ingot on the left says that this ingot is made from 50 liang of gold with 80% purity purchased in the western seas in the 17th year of the Yongle Emperor (1419). On July 17th, in the seventh year of the reign of Yongle (1419), Zheng He brought his fifth expedition back from the western ocean. This inscription tells us that the gold used to cast this ingot was purchased by Zheng He's fleet in the western ocean. To date, this is the only relic with an inscription relating to Zheng He's voyages ever found.