https://daytonart.emuseum.com/objects/4869/snuff-bottle-with-stopper
https://www.reddit.com/r/ArtefactPorn/comments/1kvvn3q/snuff_bottle_shaped_like_corn_carved_out_of/
From the comments:
Maize was introduce to China in the middle of the 16th Century and spread pretty rapidly through the region. It appears to have been a major driver of the rapid population increase in the 1700s.
Alternatively from https://www.jstage.jst.go.jp/article/yakushi/125/7/125_7_583/_pdf
A certain Chinese herbal book presented to the emperor in 1505 shows a drawing of maize under the caption of Yiyi-ren (Job’s Tears). Also, a Chinese poem written around 1368 contains a term yumi, which indicates maize. These new findings offer clear evidence that maize existed in China in the pre-Columbian era, or before 1492.